hwos_code: src/divemode.asm comparison

comparison src/divemode.asm @ 623:c40025d8e750

3.03 beta released

author	heinrichsweikamp
date	Mon, 03 Jun 2019 14:01:48 +0200
parents	d866684249bd
children	cd58f7fc86db

comparison

equal deleted inserted replaced

-:02d1386429a6
+:c40025d8e750
 ;=============================================================================
 ;
-;   File divemode.asm								REFACTORED VERSION V2.99e
+;   File divemode.asm                         combined next generation V3.03.4
 ;
-;   Divemode
+;   Dive Mode
 ;
 ;   Copyright (c) 2011, JD Gascuel, HeinrichsWeikamp, all right reserved.
 ;=============================================================================
 ; HISTORY
 ;  2011-08-15 : [mH] moving from OSTC code
 #include "shared_definitions.h"			; mailbox from/to p2_deco.c
 #include "tft_outputs.inc"
 #include "strings.inc"
 #include "tft.inc"
 #include "eeprom_rs232.inc"
-#include "isr.inc"
 #include "math.inc"
 #include "wait.inc"
 #include "customview.inc"
 #include "start.inc"
 #include "adc_lightsensor.inc"
 #include "ghostwriter.inc"
 #include "i2c.inc"
 #include "calibrate.inc"
 #include "convert.inc"
+#include "surfmode.inc"
-IFDEF _rx_functions
 #include "rx_ops.inc"
-ENDIF
-	extern	TFT_dive_compass_heading
 	extern	do_line_menu
 	extern	do_main_divemenu
+	extern	menu_draw_lines_divemode
 	extern	option_save_all
 	extern	init_recording_params
+IFDEF _compass
-	;---- Private local variables -------------------------------------------------
+	extern	TFT_dive_compass_heading
+ENDIF
+;---- Private local Variables -------------------------------------------------
 	CBLOCK	local1						; max size is 16 Byte !!!
-		apnoe_timeout_counter			; timeout counter for apnoe mode
 		sensor_setpoint					; sensor ppo2 in 0.01bar for deco routine
 		check_gas_num					; used in search for best gas/dil: current gas/dil number (1-5)
 		check_gas_depth					; used in search for best gas/dil: current gas/dil change depth
 		check_gas_type					; used in search for best gas/dil: current gas/dil type
 		check_gas_O2_ratio				; used in search for best gas/dil: current gas/dil O2 ratio
 		best_gas_num					; used in search for best gas/dil: best    gas/dil number (1-5)  CAUTION: there is also a variable named best_gas_number !
 		best_gas_depth					; used in search for best gas/dil: best    gas/dil change depth
-		ppO2_min						; used in search for best gas/dil: minimum ppO2 required
+		last_pressure_velocity:2		; cached last absolute pressure for velocity calculation
-		ppO2_max						; used in search for best gas/dil: maximum ppO2 allowed
+		TFT_output_flags_1				; TFT update flags for output phase 1
-	ENDC								; used: 10 byte, remaining: 6 byte
+		TFT_output_flags_2				; TFT update flags for output phase 2
+		TFT_output_flags_3				; TFT update flags for output phase 3
+		TFT_output_flags_4				; TFT update flags for output phase 4
+		DM_flags_local					; various dive mode flags
+	ENDC								; used: 14 byte, remaining: 2 byte
 	CBLOCK	local2						; max size is 16 Byte !!!
-		average_depth_hold:4			; used to calculate the resettable average depth
+		pressure_rel_accu_trip:4		; pressure accumulator for calculating the resettable average depth
-		average_depth_hold_total:4		; used to calculate the absolute   average depth
+		pressure_rel_accu_total:4		; pressure accumulator for calculating the total dive average depth
-	ENDC								; used: 8 byte, remaining: 8 byte
+		xmitter_flags_stat				; pressure transmitter flags for status
+		xmitter_flags_mesg				; pressure transmitter flags for messages
-dmode		CODE
+		ppO2_min:2						; used in search for best gas/dil: minimum ppO2 required
+		ppO2_max_default:2				; used in search for best gas/dil: default  maximum ppO2
+		ppO2_max_deco:2					; used in search for best gas/dil: deco     maximum ppO2
+	ENDC								; used: 16 byte, remaining: 0 byte ==> FULL
+;---- Private local Flags ----------------------------------------------------
+; TFT_output_flags_1 - phase 1: every second - before deco calculations, all modes
+#DEFINE FLAG_TFT_depth_current			TFT_output_flags_1,0	; =1: show  current depth
+#DEFINE FLAG_TFT_depth_maximum			TFT_output_flags_1,1	; =1: show  maximum depth
+#DEFINE FLAG_TFT_active_gas_divemode	TFT_output_flags_1,2	; =1: show  active gas and dive mode
+#DEFINE FLAG_TFT_apnoe_surface_time		TFT_output_flags_1,3	; =1: show  apnoe mode surface time
+#DEFINE FLAG_TFT_depth_maximum_apnoe	TFT_output_flags_1,4	; =1: show  maximum depth of last apnoe dive
+#DEFINE FLAG_TFT_clear_apnoe_surface	TFT_output_flags_1,5	; =1: clear apnoe mode surface data from screen
+#DEFINE FLAG_TFT_apnoe_divetime			TFT_output_flags_1,6	; =1: show  apnoe mode dive times
+;										TFT_output_flags_1,7	; --- unused
+; TFT_output_flags_2 - phase 2: every second - before deco calculations, deco modes only
+#DEFINE FLAG_TFT_divemode_mask			TFT_output_flags_2,0	; =1: show  dive mode mask
+#DEFINE FLAG_TFT_divetime				TFT_output_flags_2,1	; =1: show  dive time
+#DEFINE FLAG_TFT_safety_stop_show		TFT_output_flags_2,2	; =1: show  safety stop
+#DEFINE FLAG_TFT_safety_stop_clear		TFT_output_flags_2,3	; =1: clear safety stop
+#DEFINE FLAG_TFT_temperature			TFT_output_flags_2,4	; =1: show  temperature (or resettable dive time when in compass view)
+;										TFT_output_flags_2,5	; --- unused
+;										TFT_output_flags_2,6	; --- unused
+;										TFT_output_flags_2,7	; --- unused
+; TFT_output_flags_3 - phase 3: every second - after deco calculations, deco modes only
+#DEFINE FLAG_TFT_clear_deco_data		TFT_output_flags_3,0	; =1: clear deco data (NDL or stop & TTS)
+#DEFINE FLAG_TFT_display_ndl_mask		TFT_output_flags_3,1	; =1: show  NDL  mask
+#DEFINE FLAG_TFT_display_deco_mask		TFT_output_flags_3,2	; =1: show  deco mask
+#DEFINE FLAG_TFT_display_ndl			TFT_output_flags_3,3	; =1: show  NDL  data
+#DEFINE FLAG_TFT_display_deco			TFT_output_flags_3,4	; =1: show  deco stop data
+#DEFINE FLAG_TFT_display_tts			TFT_output_flags_3,5	; =1: show  deco TTS  data
+;										TFT_output_flags_3,6	; --- unused
+;										TFT_output_flags_3,7	; --- unused
+; TFT_output_flags_4 - phase 4: every second - after deco calculations, all modes
+#DEFINE FLAG_TFT_customview_mask		TFT_output_flags_4,0	; =1: show  the custom view mask
+#DEFINE FLAG_TFT_sign_show				TFT_output_flags_4,1	; =1: show  the advice / attention / warning sign
+#DEFINE FLAG_TFT_sign_clear				TFT_output_flags_4,2	; =1: clear the advice / attention / warning sign
+#DEFINE FLAG_TFT_message_clear_both		TFT_output_flags_4,3	; =1: clear messages, both rows
+#DEFINE FLAG_TFT_message_clear_2nd		TFT_output_flags_4,4	; =1: clear messages, 2nd row only
+#DEFINE FLAG_TFT_velocity_show			TFT_output_flags_4,5	; =1: show  vertical velocity
+#DEFINE FLAG_TFT_velocity_clear			TFT_output_flags_4,6	; =1: clear vertical velocity
+;										TFT_output_flags_4,7	; --- unused
+; Pressure Transmitter Status
+#DEFINE transmitter1_lost				xmitter_flags_stat,0	; =1: transmitter 1 lost               is an old message
+#DEFINE transmitter1_battery			xmitter_flags_stat,1	; =1: transmitter 1 battery low        is an old message
+#DEFINE transmitter1_pres_warn			xmitter_flags_stat,2	; =1: transmitter 1 pressure warning   is an old message
+#DEFINE transmitter1_pres_att			xmitter_flags_stat,3	; =1: transmitter 1 pressure attention is an old message
+#DEFINE transmitter2_lost				xmitter_flags_stat,4	; =1: transmitter 2 lost               is an old message
+#DEFINE transmitter2_battery			xmitter_flags_stat,5	; =1: transmitter 2 battery low        is an old message
+#DEFINE transmitter2_pres_warn			xmitter_flags_stat,6	; =1: transmitter 2 pressure warning   is an old message
+#DEFINE transmitter2_pres_att			xmitter_flags_stat,7	; =1: transmitter 2 pressure attention is an old message
+; Pressure Transmitter Messages
+#DEFINE pres_customview_shown			xmitter_flags_mesg,0	; =1: pressure readings custom view has been shown before
+#DEFINE show_transmitter_attention		xmitter_flags_mesg,1	; =1: show transmitter attention
+#DEFINE show_pres_warning				xmitter_flags_mesg,2	; =1: show transmitter pressure warning
+#DEFINE show_pres_attention				xmitter_flags_mesg,3	; =1: show transmitter pressure attention
+;										xmitter_flags_mesg,4	; --- unused
+;										xmitter_flags_mesg,5	; --- unused
+;										xmitter_flags_mesg,6	; --- unused
+;										xmitter_flags_mesg,7	; --- unused
+; various Flags
+#DEFINE FLAG_backtrack_full				DM_flags_local,0		; =1: the backtracking storage is full
+#DEFINE new_deco_data_avail				DM_flags_local,1		; =1: new NDL or deco data available
+#DEFINE o2_sensors_agree				DM_flags_local,2		; =1: the ppO2 of all sensors are within the threshold range
+#DEFINE update_menu						DM_flags_local,3		; =1: redraw the dive menu
+#DEFINE FLAG_SP2_used					DM_flags_local,4		; =1: setpoint 2 has been auto-selected already
+#DEFINE FLAG_SP3_used					DM_flags_local,5		; =1: setpoint 3 has been auto-selected already
+#DEFINE FLAG_SP4_used					DM_flags_local,6		; =1: setpoint 4 has been auto-selected already
+#DEFINE FLAG_SP5_used					DM_flags_local,7		; =1: setpoint 5 has been auto-selected already
+dmode	CODE
 ;=============================================================================
 	global	diveloop
 diveloop:
-	banksel	common
+	clrf	STKPTR						; clear return addresses stack
-	call	speed_normal
-	call	diveloop_boot				; boot tasks for all modes
+	; start with a clean time base
+	bsf		reset_timebase				; request ISR to reset the main timebase,
+										; as we are in dive mode the dive timers will be reset as well
+	; reset global flags
+	clrf	DM_flags_state				; clear all flags for dive mode status
+	clrf	DM_flags_request			; clear all flags for user requests
+	clrf	DM_flags_event				; clear all flags for data recording events
+	clrf	DM_flags_layout1			; clear all flags for display control / layout (1)
+	clrf	DM_flags_layout2			; clear all flags for display control / layout (2)
+	clrf	DM_flags_message			; clear all flags for display control / messages
+	clrf	DM_flags_gas_dil			; clear all flags for display control / gases and diluents
+	bcf		dive_main_menu				; clear dive main    menu flag
+	bcf		dive_options_menu			; clear dive options menu flag
+	; reset local flags
+	clrf	TFT_output_flags_1			; clear all flags for TFT output phase 1
+	clrf	TFT_output_flags_2			; clear all flags for TFT output phase 2
+	clrf	TFT_output_flags_3			; clear all flags for TFT output phase 3
+	clrf	TFT_output_flags_4			; clear all flags for TFT output phase 4
+	clrf	xmitter_flags_stat			; clear all pressure transmitter status  flags
+	clrf	xmitter_flags_mesg			; clear all pressure transmitter message flags
+	clrf	DM_flags_local				; clear all the various other flags, too
+	; set initial screen layout
+	bcf		alt_layout_active			; default to normal layout
+	TSTOSC	opt_layout					; alternative layout enabled?
+	bsf		alt_layout_active			; YES - start with alternative layout
+	; boot tasks for all modes
+	call	diveloop_boot
 	; startup tasks for all modes
+;	clrf	CCP1CON						; stop PWM
+;	bcf		PORTC,2						; pull PWM output to GND
+;	clrf	CCPR1L						; backlight off
 	call	TFT_boot					; initialize TFT (includes clear screen)
-movlw       CCP1CON_VALUE               ; See hwos.inc
+	call	TFT_show_divemode_mask		; display static dive mode mask
-movwf       CCP1CON                     ; Power-on backlight
+	call	TFT_Display_FadeIn			; dim up the display
-	bsf		FLAG_TFT_divemode_mask		; request display of dive mode mask
+	; reload and redraw last custom view
+	movff	customview_divemode,active_customview
-	movff	customview_divemode,menupos3; reload last custom view
+	bsf		FLAG_TFT_customview_mask
-	bsf		redraw_custview_mask		; request redraw of last custom view
+	bcf		divetime_longer_1min		; the dive has just begun
-	btfsc	FLAG_apnoe_mode
+	btfsc	FLAG_apnoe_mode				; in apnea mode?
-	bsf		realdive					; set realdive flag in apnoe mode
+	bsf		divetime_longer_1min		; YES - force dive to have lasted for longer than 1 minute already
+	btfsc	sensor_override_active		; in simulator mode?
-	btfsc	FLAG_apnoe_mode				; done for apnoe or gauge mode
+	bsf		divetime_longer_1min		; YES - force dive to have lasted for longer than 1 minute already
-	bra		diveloop_loop_start
-	btfsc	FLAG_gauge_mode				; done for apnoe or gauge mode
+	bsf		trigger_pres_cur_changed	; flag that the pressures have changed to have all data...
-	bra		diveloop_loop_start
+	bsf		trigger_pres_max_changed	; ... written to the display on the first output round
-	; Deco modes
+	bsf		trigger_temp_changed		; flag that the temperature has changed to have the temperature ...
-	bsf		FLAG_TFT_active_gas_divemode; request display of gas and setpoint
+										; ... written to the display on the first output round
-	bsf		FLAG_TFT_display_ndl_mask	; request display of "NDL"
+	bsf		new_deco_data_avail			; flag that new deco engine results are available to have the initial data ...
-	; +@5 init
+										; ... written to the display on the first output round
-	clrf	WREG						; WAIT marker: display "---"
-	movff	WREG,char_I_sim_advance_time
+	; clear the resettable average depth
-	movff	WREG,int_O_alternate_ascenttime+0
+	call	clear_resettable_average_depth
-	bsf		WREG,int_not_yet_computed
-	bsf		WREG,int_invalid_flag
+;	; initial caching of new absolute and relative pressure, ISR-safe 2 byte copies
-	movff	WREG,int_O_alternate_ascenttime+1
+;	SMOVII	pressure_abs,    pressure_abs_cached
+;	SMOVII	pressure_rel_cur,pressure_rel_cur_cached
-diveloop_loop_start:
-	btfsc	FLAG_TFT_divemode_mask
+;	; initial transfer of absolute pressure to deco engine
-	call	TFT_divemode_mask
+;	MOVII	pressure_abs_cached,int_I_pres_respiration
-	btfsc	FLAG_TFT_display_ndl_mask
-	call	TFT_display_ndl_mask
+	btfsc	FLAG_apnoe_mode				; in apnoe mode?
+	bra		diveloop_1					; YES - done with initialization
-diveloop_loop:							; the dive loop starts here
+	btfsc	FLAG_gauge_mode				; NO  - in gauge mode?
-	btfss	quarter_second_update
+	bra		diveloop_1					;       YES - done with initialization
-	bra		diveloop_loop1
+	bsf		FLAG_TFT_display_ndl_mask	;       NO  - in deco mode then, display NDL mask
+	bsf		FLAG_TFT_active_gas_divemode;           - request initial display of gas and setpoint
-	; tasks any 1/4 second, any mode
-	bcf		quarter_second_update		; clear flag
+diveloop_1:
+	btfsc	reset_timebase				; has the ISR confirmed reset of the timebase meanwhile?
-	btfsc	alternative_divelayout		; in alternative layout?
+	bra		$-2							; NO - not yet, loop waiting for confirmation before entering the dive loop
-	bra		diveloop_loop1				; YES - no compass in alternative layout mode
-	movlw	index_compass_dm			; NO  - index of compass view
+diveloop_loop:
-	cpfseq	menupos3					;     - in compass view?
+	; ### the dive loop starts here ###
-	bra		diveloop_loop1				;       NO  - done
+	btfsc	trigger_full_second			; new 1/1 second?
-	call	TFT_dive_compass_heading	;       YES - update compass heading value
+	bra		diveloop_loop_2				; YES - continue with tasks every 1/1 second
-	bsf		FLAG_TFT_temp_divemode		;           - redraw temperature (is slightly affected from compass heading arrow)
+	btfsc	trigger_half_second			; NO  - new 1/2 second?
+	bra		diveloop_loop_1				;       YES - continue with tasks every 1/2 second
-diveloop_loop1:
-	btfss	onesecupdate				; next second begun?
+	; tasks every round except every 1/1 or 1/2 second
-	bra		diveloop_loop3				; NO
+IFDEF _compass
+	movlw	index_compass_dm			; index of compass view
-; tasks any new second...
+	cpfseq	active_customview			; in compass view?
-	bcf		onesecupdate				; one seconds update, clear flag here in case it's set again in ISR before all tasks are done.
+	bra		diveloop_loop_11			; NO  - continue with tasks every round
+	call	TFT_dive_compass_heading	; YES - update compass heading value
-;	###-- USE FOR DEBUG ONLY - RESETS RX CIRCUITRY --###
+	bsf		FLAG_TFT_temperature		;     - redraw temperature (will show resettable dive time now)
-;	bsf		LEDg
+ENDIF
-;	###----------------------------------------------###
+	bra		diveloop_loop_11			;     - continue tasks every round
+diveloop_loop_1:
+	; tasks every 1/2 second
+	bcf		trigger_half_second			; clear flag
+	btfsc	FLAG_gauge_mode				; in gauge mode?
+	bra		diveloop_loop_11			; YES - done with 1/2 second tasks
+	btfsc	FLAG_apnoe_mode				; NO  - in apnoe mode?
+	bra		diveloop_loop_11			; YES - done with 1/2 second tasks
+	; tasks every 1/2 second in deco modes
+	call	calc_deco_engine			; ##### calculate decompression #####
+	bra		diveloop_loop_11			; done with 1/2 second tasks
+diveloop_loop_2:
+	; tasks every 1/1 second (code includes tasks every 1/2 second that fall onto the full second)
+	bcf		trigger_full_second			; clear flag for new 1/1 second
+	bcf		trigger_half_second			; clear flag for new 1/2 second as well
+	btfss	trigger_temp_changed		; has the temperature changed?
+	bra		diveloop_loop_3				; NO  - continue with tasks every 1/1 second
+	bsf		FLAG_TFT_temperature		; YES - display temperature
+	bcf		trigger_temp_changed		;     - clear flag
+	; "future hardware will need min temperature checked every second..." (?)
+	MOVII	temperature_min,sub_a		;     - copy last temperature_min to sub_a
+	SMOVII	temperature_cur,sub_b		;     - ISR-safe 2 byte copy of current temperature to sub_b
+	call	sub16						;     - sub_c = sub_a - sub_b = temperature_min - temperature
+	btfsc	neg_flag					;     - temperature > temperature_min ?
+	bra		diveloop_loop_3				;       YES - done
+	MOVII	sub_b,temperature_min		;       NO  - store new minimum temperature
+diveloop_loop_3:
+	; tasks every 1/1 second
+	btfss	trigger_pres_cur_changed	; has the pressure changed?
+	bra		diveloop_loop_4				; NO  - continue with tasks every 1/1 second
+	; set flags
+	bcf		trigger_pres_cur_changed	; clear flag for pressure change
+	bsf		FLAG_TFT_depth_current		; set flag to display updated depth
+	; cache new absolute and relative pressure, ISR-safe 2 byte copies
+	SMOVII	pressure_abs,    pressure_abs_cached
+	SMOVII	pressure_rel_cur,pressure_rel_cur_cached
+	; transfer absolute pressure to deco engine
+	MOVII	pressure_abs_cached,int_I_pres_respiration
+	; compute absolute pressure / 10, will be used later on a couple of times
+	MOVII	pressure_abs_cached,xA
+	MOVLI	.10,xB
+	call	div16x16					; xC = xA / xB = absolute pressure / 10
+	MOVII	xC,pressure_abs_10			; store result for later use
 	; compute current depth in meters
-	SAFE_2BYTE_COPY rel_pressure,xA
+	MOVII	pressure_rel_cur_cached,xA	; copy current relative pressure to xA
-	movlw	.100
+	ADDLI	.50, xA						; add 0.5 meter = 50 mbar for rounding up/down at 0.5 meters
-	movwf	xB+0
+	MOVLI	.100,xB						; divide by 100 to turn mbar into meters
-	clrf	xB+1
+	call	div16x16					; xC = xA / xB = depth in full meters
-	call	div16x16						; xC = xA / xB, xC+0 now holds depth in full meters
+	movff	xC+0,depth_meter			; store result in depth_meter, only LSB of result needed
-	movff	xC+0,curr_depth					; store result in curr_depth
+IFDEF _ccr_pscr
-	; compute ambient pressure / 10, will be needed later
+	; adjust auto-setpoint
-	SAFE_2BYTE_COPY amb_pressure,xA
+	btfsc	FLAG_ccr_mode				; in CCR mode?
-	movlw	.10
+	call	check_dive_autosp			; YES - check for Auto-SP
-	movwf	xB+0
+ENDIF
-	clrf	xB+1
-	call	div16x16						; xC = xA / xB = p_amb / 10
+	; check for new max pressure
-	movff	xC+0,amb_press_10+0				; store result for later use
+	btfss	trigger_pres_max_changed	; has the max pressure changed?
-	movff	xC+1,amb_press_10+1				; ...
+	bra		diveloop_loop_4				; NO  - continue with tasks every 1/1 second
+	bcf		trigger_pres_max_changed	; YES - clear flag for new max pressure
-	; display depth based on full seconds interval (nicer blinking)
+	bsf		FLAG_TFT_depth_maximum		;     - set   flag for displaying new max depth
-	btfss	alternative_divelayout
+	SMOVII	pressure_rel_max,pressure_rel_max_cached ; - cache new max depth
-	rcall	TFT_output4_normal
-	btfsc	alternative_divelayout
+diveloop_loop_4:
-	rcall	TFT_output4_alternative
+	; continue tasks every 1/1 second
-	btfsc	FLAG_apnoe_mode				; in Apnoe mode?
+IFDEF _external_sensor
-	bra		diveloop_loop1_nonedeco		; YES - do Apnoe mode every second tasks
+	btfsc	FLAG_ccr_mode				; in CCR mode?
+	rcall	calc_deko_divemode_sensor	; YES - do sensor data acquisition if applicable
-; tasks any new second - only for deco modes
+	btfsc	FLAG_pscr_mode				; in pSCR mode?
-diveloop_loop1_deco:
+	rcall	calc_deko_divemode_sensor	; YES - do sensor data acquisition if applicable
-	bsf		FLAG_TFT_divemins			; display (new) dive time!
+ENDIF
-	btfsc	show_safety_stop			; show the safety stop?
-	bsf		FLAG_TFT_show_safety_stop	; YES - show/delete if done
+	btfsc	FLAG_apnoe_mode				; in apnoe mode?
+	rcall	divemode_apnoe_tasks		; YES - do 1 sec. apnoe tasks
-	btfss	alternative_divelayout
-	rcall	TFT_output1_normal
+	; display all animated (blinking) values at the beginning of each full second to have a stable timebase
-	btfsc	alternative_divelayout
+	rcall	TFT_output_1				; do display updates
-	rcall	TFT_output1_alternative
+	btfss	FLAG_apnoe_mode				; in apnoe mode?
-	call	divemode_check_for_warnings	; check for warnings
+	bra		diveloop_loop_5				; NO  - continue with deco mode tasks every 1/1 second
+	; apnoe mode tasks every 1/1 second
+	call	dive_customview_second		; do every second tasks for the custom view area
+	bra		diveloop_loop_10			; continue with common tasks every 1/1 second
+diveloop_loop_5:
+	; deco mode tasks every 1/1 second
+	bsf		FLAG_TFT_divetime			; display (new) dive time
+	rcall	safety_stop_show			; serve safety stop
+	rcall	TFT_output_2				; do display updates
+	call	divemode_check_warnings		; check for warnings
 IFDEF _rx_functions
-	btfss	FLAG_tr_enabled				; TR functions enabled?
+	btfss	tr_functions_activated		; TR functions activated?
-	bra		diveloop_loop1_deco1		; NO  - skip pressure readings part
+	bra		diveloop_loop_6				; NO  - continue with deco mode tasks every 1/2 second
 	call	get_pressure_readings		; YES - get  pressure readings
 	call	configure_sac_calculation	;     - set up SAC calculation
-diveloop_loop1_deco1:
+ENDIF
-ENDIF
+diveloop_loop_6:
-	call	calc_deco_divemode			; calculate decompression and set resulting display flags
+	; deco mode tasks every 1/1 second
+	INCI	divesecs_avg_trip			; increment the resettable dive time
-	btfss	alternative_divelayout
+	INCI	divesecs_avg_total			; increment the total dive dive time
-	rcall	TFT_output2_normal
-	btfsc	alternative_divelayout
+	btfsc	FLAG_gauge_mode				; in gauge mode?
-	rcall	TFT_output2_alternative
+	bra		diveloop_loop_7				; YES - skip deco calculations
-	bra		diveloop_loop2				; continue with common tasks
+	call	calc_deco_engine			; ##### calculate decompression #####
-; tasks any new second - only for apnoe mode
-diveloop_loop1_nonedeco:
+	btfsc	new_deco_data_avail			; new NDL or deco data available?
-	rcall	divemode_apnoe_tasks		; 1 sec. apnoe tasks
+	call	show_new_deco_data			; YES - update the display and update the decostop_active flag
-	call	customview_second			; do every-second tasks for the custom view area
-	;bra	diveloop_loop2				; common tasks
+	btfsc	decostop_active				; in deco mode?
+	bsf		FLAG_TFT_display_deco		; YES - update deco stop depth & time every second because of depth-dependent color-coding
-; continue tasks any new second, any mode
-diveloop_loop2:
+	bsf		FLAG_TFT_depth_current		; set flag to display depth (in next round, needed in deco modes irrespectively of a pressure change for color-coding and blinking effects)
-	btfsc	redraw_custview_mask		; shall we redraw the custom view mask?
-	call	customview_mask				; YES - redraw custom view mask
+diveloop_loop_7:
+	; deco mode tasks alternating every 2 seconds on timebase
-	rcall	timeout_divemode			; ** menu timeout? ** - this routine sets the required flags
+	btfss	timebase_1sec				; on even second of timebase?
-	rcall	set_dive_modes				; tests if depth > threshold
+	rcall	calc_velocity				; YES - calculate velocity and display if > threshold
-	rcall	set_min_temp				; store min. temp if required (future hardware will need this to be checked 1/second...)
+	btfsc	timebase_1sec				; on odd  second of timebase?
+	call	check_gas_best				; YES - check if a better gas cue can be given
-	btfsc	oneminupdate				; one minute tasks
-	rcall	update_divemode60			; update clock, etc.
+diveloop_loop_8:
+	; deco mode tasks alternating every 2 seconds on resettable dive time
-	bsf		FLAG_TFT_active_gas_divemode; have the gas and setpoint redrawn on every second to update setpoint display, animate the blinking, etc.
+	btfss	divesecs_avg_trip+0,0		; on even second of resettable dive time?
+	rcall	calc_average_depth			; YES - calculate average depth
-	btfss	alternative_divelayout
+	btfsc	divesecs_avg_trip+0,0		; on odd  second of resettable dive time?
-	rcall	TFT_output3_normal
+	rcall	safety_stop_control			; YES - exercise safety stop control
-	btfsc	alternative_divelayout
-	rcall	TFT_output3_alternative
+diveloop_loop_9:
+	; deco mode tasks every 1/1 second
-;	###-- USE FOR DEBUG ONLY - RESETS RX CIRCUITRY --###
+	rcall	TFT_output_3				; do display updates
-;	bcf		LEDg
-;	###----------------------------------------------###
+diveloop_loop_10:
+	; common tasks every 1/1 second
-; tasks any round, any mode
+	rcall	timeout_divemode			; check for timeout condition
-diveloop_loop3:
+	rcall	check_dive_modes			; test if depth still deeper than threshold
+	btfsc	trigger_full_minute			; has next minute begun?
+	rcall	update_divemode60			; YES - update clock, etc.
+	btfss	FLAG_oc_mode				; are we in OC mode?
+	bsf		FLAG_TFT_active_gas_divemode; NO - have the gas and setpoint redrawn on every second to update setpoint display, animate the blinking, etc.
+	btfsc	dive_main_menu				; dive mode menu shown?
+	bsf		update_menu					; YES - request update
+	rcall	TFT_output_4				; do display updates
+; tasks every round, every mode
+diveloop_loop_11:
 	call	test_switches_divemode		; check switches in dive mode
+	bra		diveloop_loop_12
-	global	diveloop_loop4
-diveloop_loop4:							; menu-exit returns here...
+	global	diveloop_menu_exit
-	btfsc	toggle_customview			; next view?
+diveloop_menu_exit:						; jump-in from menu exit
-	call	customview_toggle			; YES - show next custom view (and delete this flag)
+	bsf		FLAG_TFT_temperature		; restore temperature display or resettable dive time (was overwritten by menu)
-	btfsc	divemode_gaschange			; gas switch flag set?
+diveloop_loop_12:
+	bsf		FLAG_TFT_active_gas_divemode; redraw gas and setpoint (eventually needed to restore the "Bailout" text)
+	btfsc	request_next_custview		; shall show next custom view?
+	call	dive_customview_toggle		; YES - show next custom view (and delete this flag)
+	btfsc	request_gaschange			; shall change gas?
 	call	gas_switched_common			; YES
-	btfsc	toggle_gf					; toggle GF/aGF?
+	btfsc	request_toggle_GF			; shall toggle GF/aGF?
 	rcall	divemodemode_togglegf		; YES
 IFDEF _cave_mode
-	btfsc	toggle_turn_dive			; toggle dive turned?
+	btfsc	request_turn_dive			; shall turn dive?
 	rcall	divemodemode_toggleturn		; YES
 ENDIF
-	btfsc	FLAG_set_marker				; shall set a marker?
+	btfsc	request_set_marker			; shall set a marker?
 	call	set_logbook_marker			; YES
-	btfsc	store_sample				; shall store new sample?
+	btfsc	trigger_sample_divedata		; shall store new sample of dive data?
 	call	store_dive_data				; YES - store profile data
 	btfss	divemode					; dive finished?
-	goto	ghostwriter_end_dive		; YES - dive finished!
+	goto	ghostwriter_end_dive		; YES - dive finished
-	btfsc	pressure_refresh			; new pressure available?
-	rcall	set_max_depth				; YES - update max. depth if required
-	btfsc	pressure_refresh			; new pressure available?
-	bsf		FLAG_TFT_depth				; YES - update depth
-	bcf		pressure_refresh			; clear flag
-	btfsc	temp_changed				; temperature changed?
-	bsf		FLAG_TFT_temp_divemode		; YES - display temperature
 IFDEF _screendump
-	btfsc	enable_screen_dumps			; screen dump function enabled?
+	btfsc	screen_dump_avail			; screen dump function enabled?
 	call	TFT_dump_screen_check		; YES - check if requested and do it
 ENDIF
-	bra		diveloop_loop				; loop the dive mode
+	bra		diveloop_loop				; loop in dive mode
-;--------------------------------------------------------------------------------------------------------
-TFT_output1_normal:							; beginning of any new second - only for deco modes
-	btfsc	FLAG_TFT_divemode_mask
-	call	TFT_divemode_mask
-	btfsc	FLAG_TFT_divemins
-	call	TFT_divemins					; display (new) dive time!
-	call	customview_second				; do every-second tasks for the custom view area (in sync with the dive time) mH
-	btfsc	FLAG_TFT_show_safety_stop
-	call	TFT_show_safety_stop			; show safety stop
-	btfsc	FLAG_TFT_clear_safety_stop
-	call	TFT_clear_safety_stop			; clear safety stop
-	return
-TFT_output1_alternative:					; beginning of any new second - only for deco modes
-	btfsc	FLAG_TFT_divemode_mask_alt
-	call	TFT_divemode_mask_alternative	; alternative mask
-	btfsc	FLAG_TFT_divemins
-	call	TFT_divemins_alternative		; display (new) divetime!
-	call	customview_alternative_second	; do every-second tasks for the custom view area (in sync with the dive time) mH
-	btfsc	FLAG_TFT_big_deco_alt
-	call	TFT_big_deco_alt				; big deco, also manages alternative safety stop thus moved to first wave of outputs [rl]
-	return
-TFT_output2_normal:							; any new second - only for deco modes
-	btfsc	FLAG_TFT_display_ndl_mask
-	call	TFT_display_ndl_mask
-	btfsc	FLAG_TFT_display_ndl
-	call	TFT_display_ndl
-	btfsc	FLAG_TFT_display_deko_mask
-	call	TFT_display_deko_mask
-	btfsc	FLAG_TFT_display_deko
-	call	TFT_display_deko
-	btfsc	FLAG_TFT_display_tts
-	call	TFT_display_tts
-	return
-TFT_output2_alternative:					; any new second - only for deco modes
-	return
-TFT_output3_normal:							; tasks any new second, any mode, after deco calculations
-	btfsc	FLAG_TFT_max_depth
-	call	TFT_max_depth					; use normal max. depth
-	btfsc	FLAG_TFT_divemode_warning
-	call	TFT_divemode_warning
-	btfsc	FLAG_TFT_divemode_warning_clear
-	call	TFT_divemode_warning_clear
-	btfsc	FLAG_TFT_dive_warning_text_clear
-	call	TFT_clear_warning_text			; clear complete warnings area
-	btfsc	FLAG_TFT_dive_warning_text_clr2
-	call	TFT_clear_warning_text_2nd_row	; clear 2nd row of warnings
-	return
-TFT_output3_alternative:					; tasks any new second
-	btfsc	FLAG_TFT_max_depth
-	call	TFT_max_depth_alternative		; big max. depth
-	btfsc	FLAG_TFT_dive_warning_text_clear
-	call	TFT_clear_warning_text			; clear complete warnings area (in alt mode only 2nd row...)
-	return
-TFT_output4_normal:							; tasks any round, any mode, before deco calculations (stable timebase)
-	btfsc	FLAG_TFT_depth
-	call	TFT_depth						; display depth
-	btfsc	FLAG_TFT_active_gas_divemode
-	call	TFT_active_gas_divemode			; display gas/setpoint
-	btfsc	FLAG_TFT_temp_divemode
-	call	TFT_temp_divemode				; update temperature
-	return
-TFT_output4_alternative:					; tasks any round, any mode
-	btfsc	FLAG_TFT_depth
-	call	TFT_depth						; display new depth
-	return
 ;--------------------------------------------------------------------------------------------------------
+TFT_output_1:								; every second - before deco calculations, all mode
+	btfsc	FLAG_TFT_clear_apnoe_surface	; shall clear apnoe mode surface data from screen?
+	call	TFT_clear_apnoe_surface			; YES - clear apnoe mode surface data from screen
+	btfsc	FLAG_TFT_depth_current			; shall show depth?
+	call	TFT_show_depth					; YES - display depth
+	btfsc	FLAG_TFT_depth_maximum			; shall show max depth?
+	call	TFT_show_max_depth				; YES - display max depth
+	btfsc	FLAG_TFT_active_gas_divemode	; shall show active gas and dive mode?
+	call	TFT_show_active_gas_divemode	; YES - display gas, setpoint and mode
+	btfsc	FLAG_TFT_apnoe_surface_time		; shall show apnoe mode surface time?
+	call	TFT_show_apnoe_surface			; YES - show apnoe mode surface time
+	btfsc	FLAG_TFT_depth_maximum_apnoe	; shall show max. depth of last dive?
+	call	TFT_show_apnoe_max_depth		; YES - show max. depth of last dive
+	btfsc	FLAG_TFT_apnoe_divetime			; shall show apnoe dive time?
+	call	TFT_show_apnoe_times			; YES - show apnoe dive time?
+	clrf	TFT_output_flags_1				; mark all TFT updates done
+	return									; done
+TFT_output_2:								; every second - before deco calculations, deco modes only
+	btfsc	FLAG_TFT_divemode_mask			; shall re-draw mask?
+	call	TFT_show_divemode_mask			; YES - re-draw mask
+	btfsc	FLAG_TFT_divetime				; shall show dive time?
+	call	TFT_show_divetime				; YES - show dive time
+	btfsc	FLAG_TFT_safety_stop_show		; shall show safety stop?
+	call	TFT_safety_stop_show			; YES - show safety stop
+	btfsc	FLAG_TFT_safety_stop_clear		; shall clear safety stop?
+	call	TFT_safety_stop_clear			; YES - clear safety stop
+	btfsc	FLAG_TFT_temperature			; shall show temperature?
+	call	TFT_show_temp_divemode			; YES - display temperature (or resettable dive time)
+	clrf	TFT_output_flags_2				; mark all TFT updates done
+	goto	dive_customview_second			; do every-second tasks for the custom view area (in sync with the dive time) and return
+TFT_output_3:								; every second - after deco calculations, deco modes only
+	btfsc	FLAG_TFT_clear_deco_data		; shall clear deco data (NDL or stop & TTS)?
+	call	TFT_clear_deco_data				; YES - clear deco data (NDL or stop & TTS)
+	btfsc	FLAG_TFT_display_ndl_mask		; shall show NDL mask?
+	call	TFT_show_ndl_mask				; YES - show NDL mask
+	btfsc	FLAG_TFT_display_ndl			; shall show NDL data?
+	call	TFT_show_ndl					; YES - show NDL data
+	btfsc	FLAG_TFT_display_deco_mask		; shall show deco mask?
+	call	TFT_show_deco_mask				; YES - show deco mask
+	btfsc	FLAG_TFT_display_deco			; shall show deco stop?
+	call	TFT_show_deco					; YES - show deco stop
+	btfsc	FLAG_TFT_display_tts			; shall show deco TTS?
+	call	TFT_show_tts					; YES - show deco TTS
+	clrf	TFT_output_flags_3				; mark all TFT updates done
+	return									; done
+TFT_output_4:								; every second - after deco calculations, all modes
+	btfsc	FLAG_TFT_customview_mask		; shall redraw the custom view mask?
+	call	dive_customview_mask			; YES - redraw custom view mask
+	btfsc	FLAG_TFT_velocity_show			; shall show  vertical velocity?
+	call	TFT_velocity_show				; YES - show  vertical velocity?
+	btfsc	FLAG_TFT_velocity_clear			; shall clear vertical velocity?
+	call	TFT_velocity_clear				; YES - clear vertical velocity?
+	btfsc	FLAG_TFT_sign_show				; shall show  the advice / attention / warning sign?
+	call	TFT_divemode_sign_show			; YES - show sign
+	btfsc	FLAG_TFT_sign_clear				; shall clear the advice / attention / warning sign?
+	call	TFT_divemode_sign_clear			; YES - clear sign
+	btfsc	FLAG_TFT_message_clear_both		; shall clear all messages?
+	call	TFT_clear_message_window		; YES - clear complete message area
+	btfsc	FLAG_TFT_message_clear_2nd		; shall clear 2nd row of message area?
+	call	TFT_clear_message_window_row2	; YES - clear 2nd row of message area
+	clrf	TFT_output_flags_4				; mark all TFT updates done
+	return									; done
+;--------------------------------------------------------------------------------------------------------
 divemode_apnoe_tasks:					; 1 sec. apnoe tasks
-	call	TFT_display_apnoe_descent	; show descent timer
+	bsf		FLAG_TFT_apnoe_divetime		; show apnoe dive times (current/last dive and total)
-	call	TFT_max_depth				; use normal max. depth
+	btfsc	apnoe_at_surface			; at the surface?
+	bra		divemode_apnoe_tasks_surf	; YES  - at the surface
-	btfsc	divemode2					; time running?
+	;bra	divemode_apnoe_tasks_dive	; NO   - in dive phase
-	bra		divemode_apnoe_tasks2		; YES - new descent, reset data if flag is set
+divemode_apnoe_tasks_dive:				; apnoe mode, submerged
-	rcall	apnoe_calc_maxdepth
+	btfss	apnoe_new_dive				; new dive begun?
-	call	TFT_display_apnoe_surface
+	return								; NO  - done
-	call	TFT_display_apnoe_last_max	; show last max. depth
+	bcf		apnoe_new_dive				; YES - clear flag
-	incf	apnoe_surface_secs,F
+	bsf		FLAG_TFT_clear_apnoe_surface;     - clear apnoe mode surface data from screen
-	movlw	d'60'
+	return								;     - done
-	cpfseq	apnoe_surface_secs
-	bra		divemode_apnoe_tasks1
+divemode_apnoe_tasks_surf:				; apnoe mode, at the surface
-	clrf	apnoe_surface_secs
+	bsf		FLAG_TFT_apnoe_surface_time	; show apnoe mode surface time
-	incf	apnoe_surface_mins,F
+	; TODO: these outputs would need to be done only once after surfacing...
+	bsf		FLAG_TFT_depth_maximum_apnoe; show max. depth of last dive
-divemode_apnoe_tasks1:
+	bsf		FLAG_TFT_depth_maximum		; show max. depth of all  dives
-	bcf		FLAG_active_descent			; clear flag
+	;bra	apnoe_calc_maxdepth			; calculate overall max. depth and return
-	btfsc	divemode2					; time running?
-	return								; YES - return
-	bsf		FLAG_active_descent			; set flag
-	return
-divemode_apnoe_tasks2:
-	btfss	FLAG_active_descent			; are we descending?
-	return								; NO - we are at the surface
-	rcall	apnoe_calc_maxdepth			; YES
-	call	TFT_apnoe_clear_surface		; clear surface timer
-	clrf	apnoe_timeout_counter		; delete timeout
-	clrf	apnoe_surface_secs
-	clrf	apnoe_surface_mins
-	clrf	apnoe_secs
-	clrf	apnoe_mins					; reset descent time
-	movlw	.0
-	movff	WREG,max_pressure+0
-	movff	WREG,max_pressure+1			; reset max. depth
-	bcf		FLAG_active_descent			; clear flag
-	return
 	global	apnoe_calc_maxdepth
 apnoe_calc_maxdepth:
-	movff	apnoe_max_pressure+0,sub_a+0
+	MOVII	apnoe_max_pressure,     sub_a				; get max depth from all dives to far
-	movff	apnoe_max_pressure+1,sub_a+1
+	MOVII	pressure_rel_max_cached,sub_b				; get max depth of last dive
-	movff	max_pressure+0,sub_b+0
+	call	cmpU16										; sub_a - sub_b = apnoe_max_pressure - pressure_rel_max_cached
-	movff	max_pressure+1,sub_b+1
+	btfss	neg_flag									; last dive deeper than all the others before?
-	call	subU16						; sub_c = sub_a - sub_b
+	return												; NO  - done
-										; apnoe_max_pressure <  max_pressure       -> neg_flag=1
+	MOVII	pressure_rel_max_cached,apnoe_max_pressure	; YES - store new overall max depth
-										; max_pressure       <= apnoe_max_pressure -> neg_flag=0
+	return												;     - done
-	btfss	neg_flag
-	return
-										;apnoe_max_pressure<max_pressure
-	movff	max_pressure+0,apnoe_max_pressure+0
-	movff	max_pressure+1,apnoe_max_pressure+1
-	return
 	; --------------------------------------------------------------------------------------
-calc_deco_divemode:
+calc_deco_engine:
-	btfss	FLAG_gauge_mode				; in gauge mode?
-	rcall	calc_deko_engine			; NO - do deco calculations
-	; Increment the time accumulators used for calculating the average depths.
-	; This done here and not in the ISR to guarantee synchronism between time
-	; and depth accumulator incrementing.
-	infsnz	average_divesecs+0,F
-	incf	average_divesecs+1,F
-	infsnz	average_divesecs_total+0,F
-	incf	average_divesecs_total+1,F
-	btg		onesectoggle				; toggle the one-second toggle bit
-	btfss	onesectoggle				; toggle bit set?
-	bra		calc_deko_divemode2			; NO
-	;bra	calc_deko_divemode1			; YES
-calc_deko_divemode1:					; every-2-seconds tasks, 1st phase
-;	call	TFT_debug_output			; optional debug output
-	btfsc	FLAG_gauge_mode				; in gauge mode?
-	return								; YES - done
-	goto	check_gas_best			; NO  - checks if a better gas should be selected (by user) and return
-calc_deko_divemode2:					; every-2-seconds tasks, 2nd phase
-	call	calc_average_depth			; calculate average depth
-	call	calc_velocity				; calculate vertical velocity and display if > threshold (every two seconds)
-	goto	set_reset_safety_stop		; set/reset flags for safety stop and return
-calc_deko_engine:
-	btfsc	FLAG_ccr_mode				; in CCR mode?
-	call	check_dive_autosp			; YES - check for Auto-SP
-	btfsc	FLAG_ccr_mode				; in CCR mode?
-	rcall	calc_deko_divemode_sensor	; YES - do sensor data acquisition if applicable by OSTC model
-	btfsc	FLAG_pscr_mode				; in pSCR mode?
-	rcall	calc_deko_divemode_sensor	; YES - do sensor data acquisition if applicable by OSTC model
 	; check deco engine state and switch between normal and alternative plan calculations
 	;
 	; Remark: Any reconfigurations done here do only affect the ascent & deco calculation settings,
 	;         not the settings for the calculations done on the real tissues. The later ones are only
 	;         altered in case of a gas change, or in case of a real bailout or switchback to setpoint
 	;         or sensor, respectively.
 	;         In case of a gas change or real bailout/switchback, the settings for the deco calculations
 	;         are also changed to match the settings for the real tissues. This is done on signal through
-	;         'divemode_gaschange' and will also leave the deco engine status in state as if having done
+	;         'request_gaschange' and will also leave the deco engine status in state as if having done
 	;         the alternative plan last.
 	; get working copies of char_O_main_status and char_O_deco_status
 	movff	char_O_main_status,hi		; get char_O_main_status into hi
 	movff	char_O_deco_status,lo		; get char_O_deco_status into lo
 	; check state of deco calculations
-	btfsc	hi,DECO_COMPLETED_NORM		; finished calculations for normal plan?
+	btfsc	lo,DECO_COMPLETED_NORM		; finished calculations for normal plan?
-	bra		calc_deko_engine_alt		; YES - do an alternative plan next (or a normal one with more features enabled)
+	bra		calc_deco_engine_alt		; YES - do an alternative plan next (or a normal one with more features enabled)
-	btfsc	hi,DECO_COMPLETED_ALT		; finished calculations for alternative plan?
+	btfsc	lo,DECO_COMPLETED_ALT		; finished calculations for alternative plan?
-	bra		calc_deko_engine_norm		; YES - do a normal plan next
+	bra		calc_deco_engine_norm		; YES - do a normal plan next
-	bra		calc_deko_engine_cont		; NO to both - continue calculations / do first invocation in INIT mode
+	bra		calc_deco_engine_cont		; NO to both - continue calculations / do first invocation in INIT mode
-calc_deko_engine_norm:
+calc_deco_engine_norm:
 	; Last cycle did an alternative plan, or the deco engine has been restarted because of a gas change etc.
 	; --> Reconfigure to normal plan for next computation cycle.
-	bcf		lo,DECO_PLAN_FLAG			; clear flag for alternative plan to do a normal plan next
+	bcf		lo,DECO_COMPLETED_ALT		; clear flag indicating last plan was an alternative one
+	bsf		lo,DECO_START_NORM			; set   flag to calculate a normal deco plan next
 	bcf		lo,DECO_ASCENT_FLAG			; clear flag for delayed ascent calculation
-	bcf		lo,DECO_VOLUME_FLAG			; clear flag for gas needs calculation
 	bcf		lo,DECO_BAILOUT_FLAG		; clear flag for bailout mode
+	bcf		hi,DECO_VOLUME_FLAG			; clear flag for gas needs calculation
 IFDEF _cave_mode
 	bcf		hi,DECO_CAVE_MODE			; clear flag for cave mode
 ENDIF
+IFDEF _ccr_pscr
 	btfsc	FLAG_ccr_mode				; in CCR mode?
-	bra		calc_deko_engine_norm_loop	; YES - reload diluents and reconfigure CCR mode if not in bailout
+	bra		calc_deco_engine_norm_loop	; YES - reload diluents and reconfigure CCR mode if not in bailout
 	btfsc	FLAG_pscr_mode				; in pSCR mode?
-	bra		calc_deko_engine_norm_loop	; YES - reload diluents and reconfigure pSCR mode if not in bailout
+	bra		calc_deco_engine_norm_loop	; YES - reload diluents and reconfigure pSCR mode if not in bailout
-	;bra	calc_deko_engine_norm_OC	; neither in CCR nor pSCR mode, so reload OC gases and reconfigure OC mode
+	;bra	calc_deco_engine_norm_OC	; neither in CCR nor pSCR mode, so reload OC gases and reconfigure OC mode
 										; (first cycle omits gas needs calculation for faster first deco results)
-calc_deko_engine_norm_OC:
+ENDIF
+calc_deco_engine_norm_OC:
 	movff	active_gas,WREG				; get current OC gas
 	call	deco_setup_oc_gases_pre		; set up deco calculations in OC mode with OC gases
-	bra		calc_deko_engine_start		; start deco engine
+	bra		calc_deco_engine_start		; start deco engine
-calc_deko_engine_norm_loop:				; switch to loop calculation if not in a real bailout situation
+IFDEF _ccr_pscr
-	btfsc	FLAG_bailout_mode			; check if a real bailout situation is present
+calc_deco_engine_norm_loop:				; switch to loop calculation if not in a real bailout situation
-	bra		calc_deko_engine_norm_OC	; YES - revert to OC mode
+	btfsc	bailout_mode				; check if a real bailout situation is present
+	bra		calc_deco_engine_norm_OC	; YES - revert to OC mode
 										; NO  - switch to loop calculation:
 	movff	active_dil,WREG				;     - get current diluent
 	call	deco_setup_cc_diluents_pre	;     - set up deco calculations in CCR/pSCR mode with diluents
-	bra		calc_deko_engine_start		;     - start deco engine
+	bra		calc_deco_engine_start		;     - start deco engine
+ENDIF
-calc_deko_engine_alt:
+calc_deco_engine_alt:
 	; A normal plan was computed in the last cycle. For the next calculation cycle the mode may be switched
 	; to alternative plan, or stay in normal plan but with certain features enabled...
 	bcf		lo,DECO_ASCENT_FLAG			; clear flag for delayed ascent calculation
-	bcf		lo,DECO_VOLUME_FLAG			; clear flag for gas needs calculation
 	bcf		lo,DECO_BAILOUT_FLAG		; clear flag for bailout mode
+	bcf		hi,DECO_VOLUME_FLAG			; clear flag for gas needs calculation
 IFDEF _cave_mode
 	bcf		hi,DECO_CAVE_MODE			; clear flag for cave mode
 ENDIF
-	btfsc	FLAG_bailout_mode			; check if a real bailout situation is present
+	btfsc	bailout_mode				; check if a real bailout situation is present
-	bra		calc_deko_engine_alt_1		; YES - stay in normal plan mode and preclude delayed ascent calculation
+	bra		calc_deco_engine_alt_1		; YES - stay in normal plan mode and preclude delayed ascent calculation
 	TSTOSS	char_I_extra_time			; NO  - check if a delayed ascent is enabled
-	bra		calc_deko_engine_alt_1		;       NO  - stay in normal plan mode and preclude delayed ascent calculation
+	bra		calc_deco_engine_alt_1		;       NO  - stay in normal plan mode and preclude delayed ascent calculation
-	bsf		lo,DECO_PLAN_FLAG			;       YES - set flag for alternative plan
+	bcf		lo,DECO_COMPLETED_NORM		;       YES - clear flag indicating last plan was a normal one
-	bsf		lo,DECO_ASCENT_FLAG			;           - set flag for delayed ascent
+	bsf		lo,DECO_START_ALT			;           - set   flag to calculate an alternative deco plan next
+	bsf		lo,DECO_ASCENT_FLAG			;           - set   flag for delayed ascent
-calc_deko_engine_alt_1:
+calc_deco_engine_alt_1:
 	TSTOSS	opt_calc_asc_gasvolume		; check if gas volume calculation is enabled
-	bra		calc_deko_engine_start		; NO  - no volume calculation, no simulated bailout plan in this case
+	bra		calc_deco_engine_start		; NO  - no volume calculation, no simulated bailout plan in this case
-	bsf		lo,DECO_VOLUME_FLAG			; YES - set gas needs calculation flag
+	bsf		hi,DECO_VOLUME_FLAG			; YES - set gas needs calculation flag
-	btfsc	FLAG_bailout_mode			; check if a real bailout situation is present
+	btfsc	bailout_mode				; check if a real bailout situation is present
-	bra		calc_deko_engine_start		; YES - normal plan already does bailout (OC) calculation "for real"
+	bra		calc_deco_engine_start		; YES - normal plan already does bailout (OC) calculation "for real"
 IFDEF _cave_mode
 	bsf		hi,DECO_CAVE_MODE			; activate cave mode by default
-	btfss	FLAG_cave_mode				; cave mode switched on?
+	btfss	cave_mode					; cave mode switched on?
 	bcf		hi,DECO_CAVE_MODE			; NO  - deactivate p2deco cave mode again
-	btfsc	FLAG_dive_turned			; dive turned?
+	btfsc	dive_turned					; dive turned?
 	bcf		hi,DECO_CAVE_MODE			; YES - deactivate p2deco cave mode again
-	btfsc	FLAG_cave_mode_shutdown		; cave mode function shut down?
+	btfsc	FLAG_backtrack_full			; backtracking storage full?
 	bcf		hi,DECO_CAVE_MODE			; YES - deactivate p2deco cave mode again
 ENDIF
 	btfss	lo,DECO_MODE_LOOP_FLAG		; NO  - has a loop mode calculation been done during the normal plan?
-	bra		calc_deko_engine_start		;       NO  - when not in loop mode, no simulated bailout to be done
+	bra		calc_deco_engine_start		;       NO  - when not in loop mode, no simulated bailout to be done
 	decf	best_gas_number,W			;       YES - get best gas number -1 into WREG. If not available, WREG will be 255 now. If not computed yet, WREG will be 254 now.
 	btfsc	WREG,7						;           - WREG < 128 (a bailout gas is available)?
-	bra		calc_deko_engine_alt_2		;             NO  - no simulated bailout possible because no bailout gas available to switch to
+	bra		calc_deco_engine_alt_2		;             NO  - no simulated bailout possible because no bailout gas available to switch to
-	bsf		lo,DECO_PLAN_FLAG			;             YES - set flag for alternative plan
+	bcf		lo,DECO_COMPLETED_NORM		;             YES - clear flag indicating last plan was a normal one
-	bsf		lo,DECO_BAILOUT_FLAG		;                 - set bailout mode flag (enables gas changes before 1st stop)
+	bsf		lo,DECO_START_ALT			;                 - set   flag to calculate an alternative deco plan next
+	bsf		lo,DECO_BAILOUT_FLAG		;                 - set   flag for bailout mode (enables gas switches before 1st stop)
 	movf	best_gas_number,W			;                 - put number of best gas into WREG
 	call	deco_setup_oc_gases_pre		;                 - set up deco calculations in OC mode with OC gases
-	bra		calc_deko_engine_start		;                 - start in alternative plan mode
+	bra		calc_deco_engine_start		;                 - start in alternative plan mode
-calc_deko_engine_alt_2:
+calc_deco_engine_alt_2:
-	bcf		lo,DECO_PLAN_FLAG			; clear flag for alternative plan
+	bcf		lo,DECO_START_ALT			; clear flag to calculate an alternative deco plan next
+	bsf		lo,DECO_START_NORM			; set   flag to calculate a  normal      deco plan next
 	bcf		lo,DECO_ASCENT_FLAG			; clear flag for delayed ascent calculation
-	bcf		lo,DECO_VOLUME_FLAG			; clear flag for gas needs calculation
+	bcf		hi,DECO_VOLUME_FLAG			; clear flag for gas needs calculation
 IFDEF _cave_mode
 	bcf		hi,DECO_CAVE_MODE			; clear flag for cave mode
 ENDIF
 	call	inval_alternative_plan_data	; invalidate all alternative (bailout) plan data because they are not applicable any more
-calc_deko_engine_start:
+calc_deco_engine_start:
-IFDEF _cave_mode
 	movff	hi,char_O_main_status		; write-back char_O_main_status to deco engine interface
-ENDIF
 	movff	lo,char_O_deco_status		; write-back char_O_deco_status to deco engine interface
-calc_deko_engine_cont:
+calc_deco_engine_cont:
-	SAFE_2BYTE_COPY amb_pressure,int_I_pres_respiration ; transfer ambient pressure to deco engine
+;	+++++++++++++++++++++++++++++++++++++
-	clrf	TMR5L						; restart timer used to preempt stops calculation
+	call	deco_calc_hauptroutine		; invoke the deco engine (C-code)
-	clrf	TMR5H						;
+	banksel	common						; back to bank common
-	call	deco_calc_hauptroutine		; invoke the deco engine (p2_deco.c)
+;	+++++++++++++++++++++++++++++++++++++
-	banksel	common
+	call	TFT_debug_output			; debug output of scheduling performance data
-	; check if display shall be updated due to deco engine restart
-	btfsc	FLAG_TFT_display_ndl_or_deko; shall update immediately?
-	bra		calc_deko_engine_update		; YES
 	; check if new calculation results for normal plan mode are available
-	movff	char_O_main_status,WREG		; get deco status of deco engine
+	movff	char_O_deco_status,WREG		; get deco status of deco engine
-	btfss	WREG,DECO_COMPLETED_NORM	; new calculation results for normal plan available?
+	btfsc	WREG,DECO_COMPLETED_NORM	; new calculation results for normal plan available?
-	return								; NO  - done
+	bsf		new_deco_data_avail			; YES - set flag for new NDL or deco data available
+	return								; done
-calc_deko_engine_update:
-	bcf		FLAG_TFT_display_ndl_or_deko; YES - reset flag for immediate update
-	movff	char_O_deco_info,WREG		;     - get deco info vector
+show_new_deco_data:
-	btfsc	WREG,deco_ceiling			;     - ceiling depth > 0 ?
+	bcf		new_deco_data_avail			; reset flag for new NDL or deco data available
-	bra		calc_deko_engine_update_deco;       YES - in deco
+	movff	char_O_deco_info,WREG		; get the deco info vector
-	;bra	calc_deko_engine_update_NDL	;       NO  - within NDL
+	btfsc	WREG,deco_stops				; deco stops found?
+	bra		show_new_deco_data_deco		; YES - in deco
-calc_deko_engine_update_NDL:			; within NDL
+	;bra	show_new_deco_data_ndl		; NO  - within NDL
+show_new_deco_data_ndl:					; within NDL
 	btfsc	decostop_active				; been in deco mode before?
-	bsf		FLAG_TFT_display_ndl_mask	; YES - clear deco data, display NDL time
+	bsf		FLAG_TFT_clear_deco_data	; YES - clear old deco data
+	btfsc	decostop_active				; been in deco mode before?
+	bsf		FLAG_TFT_display_ndl_mask	; YES - display NDL data mask
+	bcf		decostop_active				; clear flag for been in deco mode before
 	bsf		FLAG_TFT_display_ndl		; display NDL time
-	bcf		decostop_active				; clear flag for been in deco mode before
 	return
-calc_deko_engine_update_deco:			; in deco
+show_new_deco_data_deco:				; in deco
-	btfss	decostop_active				; already been in deco mode before?
+	btfss	decostop_active				; been in deco mode before?
-	bsf		FLAG_TFT_display_deko_mask	; NO - clear NDL time, display deco data
+	bsf		FLAG_TFT_clear_deco_data	; NO - clear old deco data
-	bsf		FLAG_TFT_display_deko		; display deco data
+	btfss	decostop_active				; been in deco mode before?
-	bsf		FLAG_TFT_display_tts		; display TTS
+	bsf		FLAG_TFT_display_deco_mask	; NO - display deco data mask
 	bsf		decostop_active				; set flag for being in deco mode
+	bsf		FLAG_TFT_display_tts		; display TTS time (display or stop data is managed somewhere else)
 	return
-	; --------------------------------------------------------------------------------------
+;=============================================================================
+IFDEF _external_sensor
 	global	calc_deko_divemode_sensor
 calc_deko_divemode_sensor:
 	; sensor acquisition code
-	btfss	s8_digital						 ; check if we have a digital interface to the sensors
+	btfss	s8_digital_avail				 ; do we have a digital S8 interface?
 	bra		calc_deko_divemode_sensor_analog ; NO  - check if we have an analog interface
-	btfss	new_s8_data_available			 ; YES - check if a new data frame was received
+	btfss	trigger_S8_data_update			 ; YES - check if a new data frame was received
-	bra		calc_deko_divemode_sensor_common ; NO  - use old values
+	bra		calc_deko_divemode_sensor_common ;       NO  - use old values
-	call	compute_mvolts_for_all_sensors	 ; YES - compute mV values from digital data
+	bcf		trigger_S8_data_update			 ;       YES - clear update flag
+	call	compute_mvolts_for_all_sensors	 ;           - compute mV values from digital data
 	bra		calc_deko_divemode_sensor_common
 calc_deko_divemode_sensor_analog:
 	btfss	analog_o2_input					; do we have an analog input?
 	bra		calc_deko_divemode_sensor_opt	; NO  - check if we have an optical interface
 	call	get_analog_inputs				; YES - get the analog voltages and continue with the common part
 	bra		calc_deko_divemode_sensor_common
 calc_deko_divemode_sensor_opt:
 	btfss	optical_input					; do we have an optical input?
 	return									; NO  - return (we have no sensors at all: not analog, not S8 and not optical)
-	btfss	sensor1_active					; YES - o2_ppo2_sensor1, o2_ppo2_sensor2 and o2_ppo2_sensor3 are already filled in ISR
+	btfss	sensor1_active					; YES - sensor1_ppO2, sensor2_ppO2 and sensor3_ppO2 are already filled in ISR
 	bcf		use_O2_sensor1					;       check HUD status data and eventually clear use_O2_sensorX
 	btfss	sensor2_active
 	bcf		use_O2_sensor2
 	btfss	sensor3_active
 	bcf		use_O2_sensor3
 	; check sensor 1
 	btfss	sensor1_calibrated_ok		; check if sensor is usable at all
 	bra		check_sensor_1_fail			; NO  - handle it as failed
 	; check min threshold
-	movff	o2_mv_sensor1+0,sub_a+0		; load sensor mV value
+	SMOVII	sensor1_mv,sub_a			; load sensor mV value
-	movff	o2_mv_sensor1+1,sub_a+1
 	rcall	check_min_threshold
 	btfsc	neg_flag					; check if result is negative, i.e. sensor_mv < min_mv
 	bra		check_sensor_1_fail			; YES - declare sensor as failed
 	; check max_threshold
 	rcall	check_max_threshold
 	btfss	hud_connection_ok			; check if there is a HUD connected
 	bra		check_sensor_1_ok			; NO  - all checks done then and positive
 	btfss	sensor1_active				; YES - HUD status ok?
 	bra		check_sensor_1_fail			;       NO - HUD reports a fail
 check_sensor_1_ok:
-	; o2_ppo2_sensor1 = o2_mv_sensor1:2 * opt_x_s1:2 / 1000
+	; sensor1_ppO2 = sensor1_mv:2 * opt_x_s1:2 / 1000
-	movff	o2_mv_sensor1+0,xA+0
+	SMOVII	sensor1_mv,xA
-	movff	o2_mv_sensor1+1,xA+1
+	MOVII	opt_x_s1,  xB
-	movff	opt_x_s1+0,xB+0
-	movff	opt_x_s1+1,xB+1
 	rcall	compute_ppo2_helper
-	movff	xC+0,o2_ppo2_sensor1		; result in 0.01 bar
+	movff	xC+0,sensor1_ppO2			; result in 0.01 bar
 	bra		check_sensor_2				; continue with next sensor
 check_sensor_1_fail:
 	clrf	WREG
-	movff	WREG,o2_ppo2_sensor1		; set ppO2 reading to zero
+	movff	WREG,sensor1_ppO2			; set ppO2 reading to zero
 	btfss	use_O2_sensor1				; check if sensor was in use before
 	bra		check_sensor_1_fail_1		; NO  - no new news then
-	call	check_sensor_custview_helper; YES - show customview 1 (sensor values) on further conditions met
+	call	check_sensor_custview_helper; YES - show sensors custom view on further conditions met
 check_sensor_1_fail_1:
 	bcf		use_O2_sensor1				; revoke sensor from usage
 check_sensor_2:							; check min_mv of sensor 2
 	btfss	sensor2_calibrated_ok		; check if sensor is usable at all
 	bra		check_sensor_2_fail			; NO  - handle it as failed
 	; check min threshold
-	movff	o2_mv_sensor2+0,sub_a+0		; load sensor mV value
+	SMOVII	sensor2_mv,sub_a			; load sensor mV value
-	movff	o2_mv_sensor2+1,sub_a+1
 	rcall	check_min_threshold
 	btfsc	neg_flag					; check if result is negative, i.e. sensor_mv < min_mv
 	bra		check_sensor_2_fail			; YES - declare sensor as failed
 	; check max_threshold
 	rcall	check_max_threshold
 	btfss	hud_connection_ok			; check if there is a HUD connected
 	bra		check_sensor_2_ok			; NO  - all checks done then and positive
 	btfss	sensor2_active				; YES - HUD status ok?
 	bra		check_sensor_2_fail			;       NO - HUD reports a fail
 check_sensor_2_ok:
-	; o2_ppo2_sensor2 = o2_mv_sensor2:2 * opt_x_s2:2 / 1000
+	; sensor2_ppO2 = sensor2_mv:2 * opt_x_s2:2 / 1000
-	movff	o2_mv_sensor2+0,xA+0
+	SMOVII	sensor2_mv,xA
-	movff	o2_mv_sensor2+1,xA+1
+	MOVII	opt_x_s2,  xB
-	movff	opt_x_s2+0,xB+0
-	movff	opt_x_s2+1,xB+1
 	rcall	compute_ppo2_helper
-	movff	xC+0,o2_ppo2_sensor2		; result in 0.01 bar
+	movff	xC+0,sensor2_ppO2			; result in 0.01 bar
 	bra		check_sensor_3				; continue with next sensor
 check_sensor_2_fail:
 	clrf	WREG
-	movff	WREG,o2_ppo2_sensor2		; set ppO2 reading to zero
+	movff	WREG,sensor2_ppO2			; set ppO2 reading to zero
 	btfss	use_O2_sensor2				; check if sensor was in use before
 	bra		check_sensor_2_fail_1		; NO  - no new news then
-	call	check_sensor_custview_helper; YES - show customview 1 (sensor values) on further conditions met
+	call	check_sensor_custview_helper; YES - show sensors custom view on further conditions met
 check_sensor_2_fail_1:
 	bcf		use_O2_sensor2				; revoke sensor from usage
 check_sensor_3:							; check min_mv of sensor 2
 	btfss	sensor3_calibrated_ok		; check if sensor is usable at all
 	bra		check_sensor_3_fail			; NO  - handle it as failed
 	; check min threshold
-	movff	o2_mv_sensor3+0,sub_a+0		; load sensor mV value
+	SMOVII	sensor3_mv,sub_a			; load sensor mV value
-	movff	o2_mv_sensor3+1,sub_a+1
 	rcall	check_min_threshold
 	btfsc	neg_flag					; check if result is negative, i.e. sensor_mv < min_mv
 	bra		check_sensor_3_fail			; YES - declare sensor as failed
 	; check max threshold
 	rcall	check_max_threshold
 	btfss	hud_connection_ok			; check if there is a HUD connected
 	bra		check_sensor_3_ok			; NO  - all checks done then and positive
 	btfss	sensor3_active				; YES - HUD status ok?
 	bra		check_sensor_3_fail			;       NO - HUD reports a fail
 check_sensor_3_ok:
-	; o2_ppo2_sensor3 = o2_mv_sensor3:2 * opt_x_s1:2 / 1000
+	; sensor3_ppO2 = sensor3_mv:2 * opt_x_s1:2 / 1000
-	movff	o2_mv_sensor3+0,xA+0
+	SMOVII	sensor3_mv,xA
-	movff	o2_mv_sensor3+1,xA+1
+	MOVII	opt_x_s3,  xB
-	movff	opt_x_s3+0,xB+0
-	movff	opt_x_s3+1,xB+1
 	rcall	compute_ppo2_helper
-	movff	xC+0,o2_ppo2_sensor3		; result in 0.01 bar
+	movff	xC+0,sensor3_ppO2			; result in 0.01 bar
 	bra		calc_deko_divemode_sensor_A	; continue with calculating sensor average
 check_sensor_3_fail:
 	clrf	WREG
-	movff	WREG,o2_ppo2_sensor3		; set ppO2 reading to zero
+	movff	WREG,sensor3_ppO2			; set ppO2 reading to zero
 	btfss	use_O2_sensor3				; check if sensor was in use before
 	bra		check_sensor_3_fail_1		; NO  - no new news then
-	call	check_sensor_custview_helper; YES - show custom view 1 (sensor values) on further conditions met
+	call	check_sensor_custview_helper; YES - show sensors custom view on further conditions met
 check_sensor_3_fail_1:
 	bcf		use_O2_sensor3				; revoke sensor from usage
 calc_deko_divemode_sensor_A:			; calculate sensor average
-	; exit here if not in dive mode
+	btfss	divemode					; in dive mode?
-	btfss	divemode
+	return								; NO - done here if not in dive mode
-	return
 	; compute sensor_setpoint = average of all o2_ppo2_sensorX of those sensors that have use_O2_sensorX == true
 	; sum up sensor values (in xA:2) and active sensors in (xB:2)
-	clrf	xB+0
+	CLRI	xA
-	clrf	xB+1
+	CLRI	xB
-	clrf	xA+0
-	clrf	xA+1
 divemode_setup_sensor_1_value:
-	btfss	use_O2_sensor1					; sensor1 active?
+	btfss	use_O2_sensor1					; sensor 1 active?
 	bra		divemode_setup_sensor_2_value	; NO
-	movf	o2_ppo2_sensor1,W
+	movff	sensor1_ppO2,WREG
 	addwf	xA+0,F
 	movlw	.0
 	addwfc	xA+1,F							; add into xA:2
 	incf	xB+0,F							; add a sensor
 divemode_setup_sensor_2_value:
-	btfss	use_O2_sensor2					; sensor2 active?
+	btfss	use_O2_sensor2					; sensor 2 active?
 	bra		divemode_setup_sensor_3_value	; NO
-	movf	o2_ppo2_sensor2,W
+	movff	sensor2_ppO2,WREG
 	addwf	xA+0,F
 	movlw	.0
 	addwfc	xA+1,F							; add into xA:2
 	incf	xB+0,F							; add a sensor
 divemode_setup_sensor_3_value:
-	btfss	use_O2_sensor3					; sensor3 active?
+	btfss	use_O2_sensor3					; sensor 3 active?
 	bra		divemode_setup_sensor_mean		; NO
-	movf	o2_ppo2_sensor3,W
+	movff	sensor3_ppO2,WREG
 	addwf	xA+0,F
 	movlw	.0
 	addwfc	xA+1,F							; add into xA:2
 	incf	xB+0,F							; add a sensor
 	call	div16x16						; NO - execute xC = xA / xB = summed ppO2 / number of sensors
 	movff	xC+0,sensor_setpoint			; copy result (or its default)
 	; set default value for pSCR mode: 0 => let p2_deco.c compute the ppO2 based on current dil gas and depth
 	; will be overwritten later in case we are in sensor mode and have at least one usable sensor
-	clrf	WREG								; preload a zero
+	clrf	WREG								; pre-load a zero
 	btfsc	FLAG_pscr_mode						; check if we are in pSCR mode
 	movff	WREG,char_I_const_ppO2				; YES - write 0 to char_I_const_ppo2,
 												;       it will be overwritten if we have a usable sensor reading
-	btfsc	FLAG_bailout_mode					; check if we are in bailout
+	btfsc	bailout_mode						; check if we are in bailout
 	bra		calc_deko_divemode_sensor_V			; YES - no sensor data transfer to char_I_const_ppO2 in this case
 	movff	opt_ccr_mode,WREG					; NO  - get mode (0: Fixed SP, 1: Sensor, 2: Auto SP)
 	sublw	.1									;     - in sensor mode?
 	bnz		calc_deko_divemode_sensor_V			;       NO  - not in sensor mode - no transfer of sensor data to char_I_const_ppO2
 	tstfsz	xB+0								;       YES - check if we have found at least one usable sensor
 	bra		divemode_setup_sensor_mean1			;             YES - we have at least one usable sensor
-	bsf		setpoint_fallback					;             NO  - we have NO usable sensors -> initiate fallback
+	bsf		sp_fallback							;             NO  - we have NO usable sensors -> initiate fallback
 	btfss	FLAG_ccr_mode						;                 - check if we are in CCR mode
 	bra		calc_deko_divemode_sensor_V			;                   NO  - continue with voting logic flags
-	movff	char_I_setpoint_cbar+0,char_I_const_ppO2;               YES - select fixed setpoint no. 1 for fallback
+	movff	opt_setpoint_cbar+0,char_I_const_ppO2 ;                 YES - select fixed setpoint no. 1 for fallback
 	bra		calc_deko_divemode_sensor_V			;                       - continue with voting logic flags
 	; we have at least one usable sensor with a ppO2 value > 0
 divemode_setup_sensor_mean1:
-	bcf		setpoint_fallback					; clear fallback condition
+	bcf		sp_fallback							; clear fallback condition
 	movff	sensor_setpoint,char_I_const_ppO2	; transfer average sensor value to p2_deco.c code
 	; vote sensors
 calc_deko_divemode_sensor_V:
 	bsf		voting_logic_sensor1
-	movff	o2_ppo2_sensor1,lo
+	movff	sensor1_ppO2,lo
 	rcall	check_sensor_voting_helper
 	tstfsz	WREG						; sensor within range (WREG = 0)?
 	bcf		voting_logic_sensor1		; NO - vote out this sensor
 	bsf		voting_logic_sensor2
-	movff	o2_ppo2_sensor2,lo
+	movff	sensor2_ppO2,lo
 	rcall	check_sensor_voting_helper
 	tstfsz	WREG						; sensor within range (WREG = 0)?
 	bcf		voting_logic_sensor2		; NO - vote out this sensor
 	bsf		voting_logic_sensor3
-	movff	o2_ppo2_sensor3,lo
+	movff	sensor3_ppO2,lo
 	rcall	check_sensor_voting_helper
 	tstfsz	WREG						; sensor within range (WREG = 0)?
 	bcf		voting_logic_sensor3		; NO - vote out this sensor
 	; check if a warning shall be issued on sensor disagreement
 	bra		check_warn_sensor_0			; YES - continue with further checks
 	btfsc	FLAG_pscr_mode				; check if we are in pSCR mode
 	bra		check_warn_sensor_0			; YES - continue with further checks
 	bra		check_warn_sensor_done		; not in CCR and not in pSCR, so no warning
 check_warn_sensor_0:					; we are in CCR or pSCR mode
-	btfsc	FLAG_bailout_mode			; check if we are in bailout
+	btfsc	bailout_mode				; check if we are in bailout
 	bra		check_warn_sensor_done		; YES - no warning in this case
 	movff	opt_ccr_mode,WREG			; get mode (0: Fixed SP, 1: Sensor, 2: Auto SP)
 	sublw	.1							; in sensor mode?
 	bnz		check_warn_sensor_done		; NO - not in sensor mode - no warning in this case
 	; check sensor 1
 	bra		check_warn_sensor_2			; NO  - sensor can not cause a warning then
 	btfss	use_O2_sensor1				; YES - check if sensor is in use
 	bra		check_warn_sensor_2			;       NO  - sensor can not cause a warning then
 	btfsc	voting_logic_sensor1		;       YES - check if sensor value is within agreement range
 	bra		check_warn_sensor_2			;             YES - continue with next sensor
-	bcf		sensors_agree				;             NO  - issue a warning
+	bcf		o2_sensors_agree			;             NO  - issue a warning
 	return
 	; check sensor 2
 check_warn_sensor_2:
 	btfss	sensor2_calibrated_ok		; check if sensor has a valid calibration
 	bra		check_warn_sensor_3			; NO  - sensor can not cause a warning then
 	btfss	use_O2_sensor2				; YES - check if sensor is in use
 	bra		check_warn_sensor_3			;       NO  - sensor can not cause a warning then
 	btfsc	voting_logic_sensor2		;       YES - check if sensor value is within agreement range
 	bra		check_warn_sensor_3			;             YES - continue with next sensor
-	bcf		sensors_agree				;             NO  - issue a warning
+	bcf		o2_sensors_agree			;             NO  - issue a warning
 	return
 	; check sensor 3
 check_warn_sensor_3:
 	btfss	sensor3_calibrated_ok		; check if sensor has a valid calibration
 	bra		check_warn_sensor_agree		; NO  - sensor can not cause a warning then
 	btfss	use_O2_sensor3				; YES - check if sensor is in use
 	bra		check_warn_sensor_agree		;       NO  - sensor can not cause a warning then
 	btfsc	voting_logic_sensor3		;       YES - check if sensor value is within agreement range
 	bra		check_warn_sensor_agree		;             YES - continue with next sensor
-	bcf		sensors_agree				;             NO  - issue a warning
+	bcf		o2_sensors_agree			;             NO  - issue a warning
 	return
 	; no need for a warning
 check_warn_sensor_done:
 check_warn_sensor_agree:
-	bsf		sensors_agree
+	bsf		o2_sensors_agree
 	return
 check_min_threshold:
-	movlw	LOW  min_mv					; load minimum mV value
+	MOVLI	min_mv,sub_b				; load minimum mV value
-	movwf	sub_b+0
-	movlw	HIGH min_mv
-	movwf	sub_b+1
 	goto	sub16						; sub_c = sensor_mv - min_mv (and return)
 check_max_threshold:
-	movlw	LOW  max_mv
+	MOVLI	max_mv,sub_b				; load maximum mV value
-	movwf	sub_b+0
-	movlw	HIGH max_mv
-	movwf	sub_b+1
 	goto	sub16						; sub_c = sensor_mv - max_mv (and return)
 compute_ppo2_helper:
-	call	mult16x16					; xA:2*xB:2=xC:4
+	call	mult16x16					; xC:4 = xA:2 * xB:2
-	movlw	LOW  .1000
+	MOVLI	.1000,xB
-	movwf	xB+0
+	call	div32x16					; xC:4 = xC:4 / xB:2 with xA as remainder
-	movlw	HIGH .1000
+	tstfsz	xC+1						; is the ppO2 higher than 2.55 bar?
-	movwf	xB+1
+	setf	xC+0						; YES - set result to 255 aka 2.55 bar
-	call	div32x16					; xC:4 / xB:2 = xC+3:xC+2 with xC+1:xC+0 as remainder
-	movlw	d'1'
-	addwf	xC+0,W						; we are just interested in the carry flag
-	movlw	d'0'
-	addwfc	xC+1,W						; we are still just interested in the carry flag
-	tstfsz	WREG						; ppO2 is higher than 2.55bar?
-	setf	xC+0						; YES
 	return
 check_sensor_custview_helper:
 	btfss	divemode					; check if we are in dive mode
 	return								; NO  - not in dive mode, return
 	movff	opt_ccr_mode,WREG			; YES - =0: Fixed SP, =1: Sensor, =2: Auto SP
 	decfsz	WREG,W						;     - opt_ccr_mode = 1 (sensors)?
 	return								;       NO  - not using the sensors in the moment
-	btfsc	alternative_divelayout		;       YES - in alternative layout?
+show_sensors_custview:
-	call	switch_layout_to_normal		;             YES - switch to normal layout
+	movlw	index_ppo2_sensors-1		;       YES - custom view number one below ppO2 sensors
-	movlw	index_ppo2_sensors-1		;             custom view number one below ppO2 sensors
+	movwf	active_customview			;           - set custom view number
-	movwf	menupos3					;             set custom view number
+	bsf		request_next_custview		;           - initiate toggle to desired custom view -> ppO2 sensors
-	bsf		toggle_customview			;             initiate toggle to desired custom view -> ppO2 sensors
 	return
 check_sensor_voting_helper:
 	movf	lo,W
 	cpfsgt	sensor_setpoint
 	; lo < sensor_setpoint
 	movf	sensor_setpoint,W
 	subwf	lo,F
 	bra		check_sensor_voting_helper1
-;-----------------------------------------------------------------------------
+ENDIF	; _external_sensor
+;=============================================================================
 divemodemode_togglegf:								; toggle aGF/GF
-	bcf		toggle_gf								; clear command flag
+	bcf		request_toggle_GF						; clear request flag
-	btg		use_agf									; toggle status flag for GF
+	btg		use_aGF									; toggle normal / alternative GF factor selection
+	btfsc	use_aGF									; alternative GF factors activated?
-	btfsc	use_agf									; aGF activated?
 	bra		divemodemode_togglegf_1					; YES - branch to using aGF
-	movff	opt_GF_low,char_I_GF_Low_percentage		; NO  - use normal GF factors
+	movff	opt_GF_low, char_I_GF_Low_percentage	; NO  - use normal GF factor low
-	movff	opt_GF_high,char_I_GF_High_percentage	;     -
+	movff	opt_GF_high,char_I_GF_High_percentage	;     - use normal GF factor high
 	bra		divemodemode_togglegf_2					;     - continue with common part
 divemodemode_togglegf_1:
-	movff	opt_aGF_low,char_I_GF_Low_percentage	; YES - use alternative GF factors
+	movff	opt_aGF_low, char_I_GF_Low_percentage	; YES - use alternative GF factor low
-	movff	opt_aGF_high,char_I_GF_High_percentage	;     -
+	movff	opt_aGF_high,char_I_GF_High_percentage	;     - use alternative GF factor high
 divemodemode_togglegf_2:
 	call	TFT_gf_factors_mask						; update custom view mask to show which one is in use
 													; the custom view itself has been called from divemenu_tree before
 	goto	restart_deco_engine						; ...and return
+;=============================================================================
 IFDEF _cave_mode
 divemodemode_toggleturn:
-	bcf		toggle_turn_dive						; clear command flag
+	bcf		request_turn_dive						; clear request flag
-	btg		FLAG_dive_turned						; toggle dive turned state
+	btg		dive_turned								; toggle dive turned state
-	btfsc	FLAG_cave_mode_shutdown					; cave mode function shut down?
+	btfsc	FLAG_backtrack_full						; backtracking storage full?
-	bsf		FLAG_dive_turned						; YES - allow only activating turned state
+	bsf		dive_turned								; YES - allow only activating turned state
 	goto	set_logbook_marker						; set a logbook marker (and return)
-ENDIF
+ENDIF
-calc_velocity:										; called every two seconds
-	btfsc	display_velocity
-	bra		calc_velocity1							; always update if already displayed
-	btfss	divemode2
-	return											; display velocity only if deeper then 1m (Not at the surface after the dive)
-calc_velocity1:
-	SAFE_2BYTE_COPY amb_pressure, sub_a
-	movff	last_pressure_velocity+0,sub_b+0
-	movff	last_pressure_velocity+1,sub_b+1
-	movff	sub_a+0,last_pressure_velocity+0		; store old value for velocity
-	movff	sub_a+1,last_pressure_velocity+1
-	call	subU16									; sub_c = amb_pressure - last_pressure
-	bcf		neg_flag_velocity
-	btfsc	neg_flag
-	bsf		neg_flag_velocity
-	movff	sub_c+0,xA+0
-	movff	sub_c+1,xA+1
-	movlw	d'39'						; 77 when called every second....
-	movwf	xB+0
-	clrf	xB+1
-	call	mult16x16					; differential pressure in mbar*77...
-	movff	xC+0,divA+0
-	movff	xC+1,divA+1
-	movlw	d'7'
-	call	div16						; divA = divA / 2^WREG, divide by 2^7 equals velocity in m/min
-	movlw	d'99'
-	cpfsgt	divA+0						; velocity > 99 m/min ?
-	bra		calc_velocity3				; NO
-	movwf	divA+0						; YES - set divA = 99
-calc_velocity3:
-	; Copy old speeds
-	movff	old_velocity+2,old_velocity+3
-	movff	old_velocity+1,old_velocity+2
-	movff	old_velocity+0,old_velocity+1
-	movff	divA+0,old_velocity+0
-;	movff	old_velocity+3,WREG
-;	addwf	divA+0,F					; add old speed
-;	bcf		STATUS,C
-;	rrcf	divA+0,F					; /2
-;	movff	old_velocity+2,WREG
-;	addwf	divA+0,F					; add old speed
-;	bcf		STATUS,C
-;	rrcf	divA+0,F					; /2
-;	movff	old_velocity+1,WREG
-;	addwf	divA+0,F					; add old speed
-;	bcf		STATUS,C
-;	rrcf	divA+0,F					; /2
-;	movff	old_velocity+0,WREG
-;	addwf	divA+0,F					; add old speed
-;	bcf		STATUS,C
-;	rrcf	divA+0,F					; /2
-	goto	TFT_display_velocity		; with divA+0 = m/min..., and return...
 ;=============================================================================
-set_reset_safety_stop:					; set flags for safety stop and/or reset safety stop
+calc_velocity:							; called every two seconds
+	btfsc	velocity_active_num			; was velocity shown in last cycle?
+	bra		calc_velocity_1				; YES - always update if shown before
+	btfss	count_divetime				; NO  - is the dive time counted, i.e. deeper than dive threshold?
+	return								;       NO - display velocity only if deeper than 1m,
+										;            i.e. not at the surface after the dive
+calc_velocity_1:
+	; calculate pressure difference
+	MOVII	pressure_abs_cached,   sub_a; current pressure
+	MOVII	last_pressure_velocity,sub_b; last pressure
+	call	subU16						; do an unsigned subtraction
+	; decide if ascending or descending
+	bcf		neg_flag_velocity			; set to ascending by default
+	btfsc	neg_flag					; pressure differential negative?
+	bsf		neg_flag_velocity			; YES - descending
+	; store current pressure as last pressure for next round
+	MOVII	pressure_abs_cached,last_pressure_velocity
+	; calculate velocity in m/min
+	MOVII	sub_c,xA					; copy pressure differential to xA
+	MOVLI	.39,xB						; put scale coefficient into xB (use 77 when called every second)
+	call	mult16x16					; compute differential pressure in mbar*39
+	MOVII	xC,divA						; copy result to divA
+	movlw	.7							; divide by 2^7
+	call	div16						; divA = divA / 2^WREG, yields velocity in m/min
+	movlw	.99							; load a 99
+	cpfslt	divA+0						; velocity < 99 m/min ?
+	movwf	divA+0						; NO  - limit to 99 m/min
+	bcf		STATUS,C					; clear carry flag
+	movlw	velocity_display_threshold	; get threshold for displaying vertical velocity
+	subwf	divA+0,W					; subtract threshold from velocity
+	btfss	STATUS,C					; above threshold?
+	bsf		FLAG_TFT_velocity_clear		; NO  - don't show / request to clear
+	btfsc	STATUS,C					; above threshold?
+	bsf		FLAG_TFT_velocity_show		; YES - request to show
+	return								; done
+;=============================================================================
+safety_stop_control:
 	TSTOSS	opt_enable_safetystop		; safety stop enabled? (=1: show safety stop)
-	bra		delete_safety_stop			; NO - don't show safety stop
+	return								; NO  - done
-	btfsc	decostop_active				; is a deco stop displayed?
+	btfsc	FLAG_gauge_mode				; in gauge mode?
-	bra		delete_safety_stop			; YES - don't show safety stop
+	return								; YES - omit (well, else fix collision of safety stop output with avg depth label)
-	; Below "opt_safety_stop_reset"? if yes, set flag and reset count-down timer
+	; setup
-	SAFE_2BYTE_COPY rel_pressure, lo
+	bcf		safety_stop_enabled			; disable safety stop by default
-	call	adjust_depth_with_salinity	; computes salinity setting into lo:hi [mbar]
-	movff	lo,sub_a+0
+	; check for deco
-	movff	hi,sub_a+1
+	btfsc	decostop_active				; in deco mode?
-	movff	opt_safety_stop_reset,WREG	; [cbar]
+	bra		safety_stop_finish			; YES - shut down safety stop
-	mullw	.10							; mbar in PRODL:H
-	movff	PRODL,sub_b+0
+	; below "opt_safety_stop_reset"?
-	movff	PRODH,sub_b+1
+	MOVII	pressure_rel_cur_cached,mpr	; get current depth into hi:lo
-	call	subU16						; sub_c = sub_a - sub_b
+	call	adjust_depth_with_salinity	; compute salinity setting into hi:lo [mbar]
-	btfss	neg_flag
+	MOVII	mpr,sub_a					; move adjusted depth to sub_a
-	bra		reset_safety_stop			; below 10m, reset safety stop
+	movff	opt_safety_stop_reset,WREG	; load safety stop reset threshold [cbar]
+	mullw	.10							; convert threshold from [cbar] to [mbar]
-	; Above "opt_safety_stop_end"? if yes ,clear flag
+	MOVII	PROD,sub_b					; move threshold to sub_b
-	movff	opt_safety_stop_end,WREG	; [cbar]
+	call	cmpU16						; sub_a - sub_b
-	mullw	.10							; mbar in PRODL:H
+	btfss	neg_flag					; below threshold depth?
-	movff	PRODL,sub_b+0				; sub_a is still loaded with adjusted rel_pressure
+	bra		safety_stop_reset			; YES - arm safety stop and delete it from display if still shown
-	movff	PRODH,sub_b+1
-	call	subU16						; sub_c = sub_a - sub_b
+	; above "opt_safety_stop_end"?
-	btfsc	neg_flag
+	movff	opt_safety_stop_end,WREG	; load safety stop end threshold [cbar]
-	bra		delete_safety_stop			; above 3m, remove safety stop
+	mullw	.10							; convert threshold from [cbar] to [mbar]
+	MOVII	PROD,sub_b					; move threshold to sub_b
-	; Above "opt_safety_stop_start"? if yes, activate safety stop
+	call	cmpU16						; sub_a - sub_b
-	movff	opt_safety_stop_start,WREG	; [cbar]
+	btfsc	neg_flag					; above or at threshold depth?
-	mullw	.10							; mbar in PRODL:H
+	bra		safety_stop_finish			; YES - finish with safety stop
-	movff	PRODL,sub_b+0				; sub_a is still loaded with adjusted rel_pressure
-	movff	PRODH,sub_b+1
+	; above "opt_safety_stop_start"?
-	call	subU16						; sub_c = sub_a - sub_b
+	movff	opt_safety_stop_start,WREG	; load safety stop start threshold [cbar]
-	btfsc	neg_flag
+	mullw	.10							; convert threshold from [cbar] to [mbar]
-	bra		acivate_safety_stop			; above 5m, activate safety stop
+	MOVII	PROD,sub_b					; move threshold to sub_b
-	bra		reset_safety_stop2			; pause safety stop
+	call	cmpU16						; sub_a - sub_b
+	btfss	neg_flag					; above or at threshold depth?
-acivate_safety_stop:
+	return								; NO  - pause safety stop
-	tstfsz	safety_stop_countdown		; countdown at zero?
+	tstfsz	safety_stop_countdown		; YES - safety stop armed?
-	bsf		show_safety_stop			; NO - set flag
+	bsf		safety_stop_enabled			;       YES - enable safety stop
-	return
+	return								;       NO  - done
-delete_safety_stop:
+safety_stop_show:
-	clrf	safety_stop_countdown		; reset timer
+	btfss	safety_stop_enabled			; safety stop enabled?
-	bra		reset_safety_stop2			; remove safety stop from display
+	return								; NO  - done
+	dcfsnz	safety_stop_countdown,F		; YES - decrement remaining stop time, reached zero?
-reset_safety_stop:
+	bra		safety_stop_finish			;       YES - finished with safety stop
-	movff	opt_safety_stop_length,safety_stop_countdown ; reset timer
+	bsf		FLAG_TFT_safety_stop_show	;       NO  - request to show safety stop
-reset_safety_stop2:
+	return								;           - done
-	bcf		show_safety_stop			; clear flag
-	btfss	safety_stop_active			; safety stop shown?
+safety_stop_finish:
-	return								; NO - don't delete it
+	clrf	safety_stop_countdown							; disarm safety stop
-	bcf		safety_stop_active			; clear flag
+	bcf		safety_stop_enabled								; disable safety stop
-	bsf		FLAG_TFT_clear_safety_stop	; Clear safety stop
+	bsf		FLAG_TFT_safety_stop_clear						; request to clear safety stop
-	return
+	return													; done
+safety_stop_reset:
+	movff	opt_safety_stop_length,safety_stop_countdown	; arm safety stop (load timer)
+	incf	safety_stop_countdown,F							; +1 because safety_stop_show does decrement first
+	bsf		FLAG_TFT_safety_stop_clear						; request to clear safety stop
+	return													; done
 ;=============================================================================
 timeout_menuview:
-	decfsz	timeout_counter2,F			; timeout for menu view?
+	btfss	trigger_timeout				; timeout occurred?
-	return								; NO - done
+	return								; NO  - done
-	; Timeout, clear e.g. "Menu?"
+	goto	menuview_toggle_reset		; YES - terminate the pre-menu and return
-	goto	menuview_toggle_reset		; ...and return
 timeout_divemode_menu:
-	decfsz	timeout_counter2,F			; timeout for divemode menu
+	btfss	trigger_timeout				; timeout occurred?
-	return
+	return								; NO  - done
+	;bra	timeout_divemode_menu2		; YES - clean up main menu and restore dive data
 	global	timeout_divemode_menu2
 timeout_divemode_menu2:					; called from divemenu_tree.asm
-	bcf		divemode_menu				; timeout, clear flag
+	bcf		dive_main_menu				; timeout, clear flag for dive mode menu shown
 	call	TFT_clear_divemode_menu		; clear menu
 	bsf		FLAG_TFT_active_gas_divemode; redraw gas/setpoint/diluent
-	bcf		blinking_better_gas			; clear flag to have temperature updated once
+	bcf		better_gas_blinking			; clear flag to have temperature updated once
-	bcf		blinking_better_dil			; clear flag to have temperature updated once
+	bcf		better_dil_blinking			; clear flag to have temperature updated once
-	bsf		FLAG_TFT_temp_divemode		; display temperature
+	bsf		FLAG_TFT_temperature		; display temperature (or resettable dive time when in compass view)
-	call	TFT_draw_gassep_line		; gas separator grid in spec mode only
+request_redraw_NDL_deco_data:
-	btfss	decostop_active				; in deco mode ?
+	btfsc	FLAG_gauge_mode				; in gauge mode?
-	bra		timeout_divemode_menu_ndl	; NO - show NDL again
+	return								; YES - done
-	; Show deco data
+	btfss	decostop_active				; NO  - in deco mode?
-	bsf		FLAG_TFT_display_deko_mask
+	bra		timeout_divemode_menu_ndl	;       NO  - show NDL  again
-	bsf		FLAG_TFT_display_deko
+	;bra	timeout_divemode_menu_deco	;       YES - show deco again
-	bsf		FLAG_TFT_display_tts
-	return
+timeout_divemode_menu_deco:
+	bsf		FLAG_TFT_display_deco_mask	; show deco mask
+	bsf		FLAG_TFT_display_deco		; show deco stop
+	bsf		FLAG_TFT_display_tts		; show TTS time
+	return								; done
 timeout_divemode_menu_ndl:
-	; Show NDL
+	bsf		FLAG_TFT_display_ndl_mask	; show NDL mask
-	bsf		FLAG_TFT_display_ndl_mask
+	bsf		FLAG_TFT_display_ndl		; show NDL time
-	bsf		FLAG_TFT_display_ndl
+	return								; done
-	return
 timeout_divemode:
-	btfsc	divemode_menu				; divemode menu active?
+	btfsc	dive_main_menu				; main dive menu shown?
-	rcall	timeout_divemode_menu		; YES - check the timeout for it...
+	rcall	timeout_divemode_menu		; YES - check the timeout for it
-	btfsc	menuview					; is a menu view shown?
+	btfsc	dive_options_menu			; pre-menu shown?
-	rcall	timeout_menuview			; YES - check the timeout for it...
+	rcall	timeout_menuview			; YES - check the timeout for it
-	btfss	realdive					; dive longer than one minute?
+	btfss	divetime_longer_1min		; does dive already last for longer than one minute?
-	return								; NO  - done
+	return								; NO  - suspend timeout
 	btfsc	FLAG_apnoe_mode				; in apnoe mode?
-	bra		timeout_divemode2			; YES - use apnoe_timeout [min] for timeout
+	bra		timeout_divemode_apnoe		; YES - use apnoe timeout
-IFNDEF __DEBUG
+IFNDEF _DEBUG
-	btfsc	simulatormode_active		; in simulator mode?
+	btfsc	sensor_override_active		; in simulator mode?
-	bra		timeout_divemode3			; YES - use simulator timeout
+	bra		timeout_divemode_sim		; YES - use simulator timeout
-ENDIF
+	;bra	timeout_divemode_dive		; NO  - use normal dive timeout
+ENDIF
-	bcf		divemode					; terminate divemode my default
-	infsnz	timeout_counter1+0,F		; increment timeout counter
+timeout_divemode_dive:
-	incf	timeout_counter1+1,F		; timeout is 16 bit counter
+	movff	opt_diveTimeout,WREG		; get dive timeout in minutes into WREG
+	;bra	timeout_divemode_com_min
-	movff	opt_diveTimeout,WREG		; get timeout in minutes
-	mullw	.60							; convert into seconds
+timeout_divemode_com_min:
-	movff	PRODL,sub_a+0
+	mullw	.60							; multiply with 60 to convert minutes in WREG to seconds
-	movff	PRODH,sub_a+1
+	MOVII	PRODL,sub_a					; copy resulting seconds to sub_a
+timeout_divemode_com_sec:
-	movff	timeout_counter1+0,sub_b+0
+	MOVII	dive_timeout_timer,sub_b	; copy current timeout timer value to sub_b
-	movff	timeout_counter1+1,sub_b+1
+	INCI	dive_timeout_timer			; increment timeout timer
-	call	subU16						; sub_c = sub_a - sub_b
+	call	cmpU16						; check sub_a - sub_b
-	btfss	neg_flag					; result negative, i.e. timeout?
+	btfsc	neg_flag					; result negative, i.e. timeout?
-	bsf		divemode					; NO - set divemode flag again
+	bcf		divemode					; YES - terminate dive mode
-	return
+	return								; done
-timeout_divemode2:
+timeout_divemode_apnoe:
-	incf	timeout_counter1+0,F		; seconds...
+	movlw	apnoe_timeout				; get apnoe timeout in minutes into WREG
-	movlw	d'60'
+	bra		timeout_divemode_com_min	; continue with common part for minutes
-	cpfseq	timeout_counter1+0			; timeout_counter1+0 = 60 ?
-	return								; No
+timeout_divemode_sim:
-	; one minute timeout done
+	MOVLI	simulator_timeout,sub_a		; get simulator timeout in seconds directly into sub_a
-	clrf	timeout_counter1+0
+	bra		timeout_divemode_com_sec	; continue with common part for seconds
-	bcf		divemode
-	incf	apnoe_timeout_counter,F
-	movlw	apnoe_timeout				; apnoe timeout [min]
+update_divemode60:						; tasks every full minute
-	cpfseq	apnoe_timeout_counter
+	bcf		trigger_full_minute			; clear flag
-	bsf		divemode
+	call	get_battery_voltage			; get battery voltage
-	return
+	rcall	set_powersafe				; check if battery is low
-timeout_divemode3:
-	bcf		divemode
-	incf	timeout_counter1+0,F
-	movlw	simulator_timeout			; simulator timeout
-	cpfsgt	timeout_counter1+0
-	bsf		divemode
-	return
-update_divemode60:						; update any minute
-	call	get_battery_voltage			; gets battery voltage
-	rcall	set_powersafe				; check if battery low
-	;call	customview_minute			; do every-minute tasks for the custom view area
-	bcf		oneminupdate
 IFDEF _cave_mode
 	movlw	.1							; prepare to add backtrack data for 1 minute
-	btfsc	FLAG_cave_mode				; cave mode enabled?
+	btfsc	cave_mode					; cave mode switched on?
-	rcall	update_backtrack			; YES - make it so
+	rcall	update_backtrack			; YES - store backtracking data
 ENDIF
-	btfss	simulatormode_active		; in simulator mode?
+	btfss	sensor_override_active		; in simulator mode?
 	return								; NO  - done
 	movlw	.20							; YES - quite dive mode simulation after 21 * 256 sec = 89 min : 36 sec
-	cpfsgt	total_divetime_seconds+1	; timeout?
+	cpfsgt	total_divetime_secs+1		;     - timeout?
-	return								; NO  - done
+	return								;       NO  - done
-IFDEF __DEBUG
+IFDEF _DEBUG
-	return								; YES -  but no timeout in debug mode
+	return								;       YES -  but no timeout in debug mode
 ENDIF
-	bra		divemode_option1			; YES - set depth to 0 m and "return"
+	bra		divemode_option1			;       YES - set depth to 0 m and "return"
+;=============================================================================
 IFDEF _cave_mode
 update_backtrack:
-	btfsc	FLAG_dive_turned			; dive turned?
+	btfsc	dive_turned					; dive turned?
 	return								; YES - done
-	movwf	lo							; store minutes to add in lo
+	movwf	lo							; NO  - store minutes to add in lo
-	lfsr	FSR1,char_I_backtrack_depth ; load FSR1 with base address of backtrack storage
+	lfsr	FSR1,char_I_backtrack_depth ;     - load FSR1 with base address of backtrack storage
-	movff	char_I_backtrack_time,FSR1L	; adjust FSR1 to last index
+	movff	char_I_backtrack_time,FSR1L	;     - adjust FSR1 to last index
 update_backtrack_loop:
-	btfsc	FLAG_cave_mode_shutdown		; backtrack storage full?
+	btfsc	FLAG_backtrack_full			;     - backtracking storage full?
-	return								; YES - done
+	return								;       YES - done
-	movff	curr_depth,PREINC1			; NO  - increment index and write current depth to backtrack storage
+	movff	depth_meter,PREINC1			;       NO  - increment index and write current depth to backtrack storage
-	incfsz	FSR1L,W						;     - did a wrap-around of the index occur (backtrack storage full)?
+	incfsz	FSR1L,W						;           - increment index once more into WREG, did a wrap-around occur (backtrack storage full)?
-	bra		update_backtrack_loop_1		;       NO  - continue loop
+	bra		update_backtrack_loop_1		;             NO  - continue loop
-	bsf		FLAG_cave_mode_shutdown		;       YES - flag backtrack storage as being full
+	bsf		FLAG_backtrack_full			;             YES - flag backtracking storage is full
-	return
+	return								;                 - done
 update_backtrack_loop_1:
 	decfsz	lo,F						; decrement loop counter, did it became zero?
 	bra		update_backtrack_loop		; NO  - loop
-	movff	FSR1L,char_I_backtrack_time	; YES - read-back index
+	movff	FSR1L,char_I_backtrack_time	; YES - store updated index
 	return								;     - done
-ENDIF
+ENDIF
-set_max_depth:
-	movff	max_pressure+0,sub_a+0
+;=============================================================================
-	movff	max_pressure+1,sub_a+1
-	SAFE_2BYTE_COPY rel_pressure, sub_b
-	call	subU16						; sub_c = sub_a - sub_b
-										; max_pressure <  rel_pressure -> neg_flag=1
-										; rel_pressure <= max_pressure -> neg_flag=0
-	btfss	neg_flag
-	return
-										; max_pressure < rel_pressure
-	movff	sub_b+0,max_pressure+0
-	movff	sub_b+1,max_pressure+1
-	bsf		FLAG_TFT_max_depth			; set flag
-	return
-set_min_temp:
-	movff	minimum_temperature+0,sub_a+0
-	movff	minimum_temperature+1,sub_a+1
-	SAFE_2BYTE_COPY temperature,sub_b
-	call	sub16						; sub_c = sub_a - sub_b
-										; minimum_temperature < T  -> neg_flag=1
-										; T <= minimum_temperature -> neg_flag=0
-	btfsc	neg_flag
-	return
-	; minimum_temperature >= T
-	movff	sub_b+0,minimum_temperature+0
-	movff	sub_b+1,minimum_temperature+1
-	return
 	global	set_dive_modes
 set_dive_modes:
-	btfsc	high_altitude_mode			; in high altitude (fly) mode?
+	SMOVII	pressure_rel_cur,sub_a		; ISR-safe 2 byte copy of current relative pressure to sub_a
-	bra		set_dive_modes3				; YES
+	bra		set_dive_modes_1
+check_dive_modes:
-set_dive_modes0:
+	MOVII	pressure_rel_cur_cached,sub_a; copy cached relative pressure to sub_a
-	movlw	LOW  start_dive_threshold
+set_dive_modes_1:
-	movwf	sub_a+0						; dive_treshold is in cm
+	btfss	high_altitude_mode			; in high altitude mode?
-	movlw	HIGH start_dive_threshold
+	bra		set_dive_modes_norm			; NO  - use normal start-dive threshold
-	movwf	sub_a+1						; dive_treshold is in cm
+	btfsc	divetime_longer_1min		; YES - dive lasted longer than one minute?
+	bra		set_dive_modes_norm			;       YES - this is a real dive -> use normal start-dive threshold
-set_dive_modes1:
+	;bra	set_dive_modes_high			;       NO  - use hight-altitude start-dive threshold
-	SAFE_2BYTE_COPY rel_pressure, sub_b
-	call	subU16						; sub_c = sub_a - sub_b
+	; high altitude start/end dive thresholds
+set_dive_modes_high:
-	btfss	neg_flag
+	btfss	count_divetime				; dive time counting, i.e. already in the dive?
-	bra		set_dive_modes2				; too shallow (rel_pressure < dive_threshold)
+	bra		set_dive_modes_high_start	; NO  - select start threshold
+	;bra	set_dive_modes_high_end		; YES - select end   threshold
-	btfsc	realdive					; dive longer than one minute?
-	clrf	timeout_counter1+0			; YES - reset timeout counter
+set_dive_modes_high_end:
+	MOVLI	dive_threshold_high_alt_end,sub_b
-	bsf		divemode					; (re-)set divemode flag
+	bra		set_dive_modes_comm
-	bsf		divemode2					; displayed divetime is running
+set_dive_modes_high_start:
+	MOVLI	dive_threshold_high_alt_start,sub_b
+	bra		set_dive_modes_comm
+	; normal altitude start/end dive thresholds
+set_dive_modes_norm:
+	btfss	count_divetime				; dive time counting, i.e. already in the dive?
+	bra		set_dive_modes_norm_start	; NO  - select start threshold
+	;bra	set_dive_modes_norm_end		; YES - select end   threshold
+set_dive_modes_norm_end:
+	MOVLI	dive_threshold_norm_alt_end,sub_b
+	bra		set_dive_modes_comm
+set_dive_modes_norm_start
+	MOVLI	dive_threshold_norm_alt_start,sub_b
+	;bra	set_dive_modes_comm
+set_dive_modes_comm:
+	call	cmpU16						; sub_a - sub_b = pressure_rel_cur - start-dive threshold
+	btfsc	neg_flag					; pressure_rel_cur > dive_threshold, i.e. deeper than threshold?
+	bra		set_dive_modes_shallow		; NO  - shallower than threshold
+	btfsc	divetime_longer_1min		; YES - dive lasted longer than one minute?
+	CLRI	dive_timeout_timer			;       YES - reset timeout counter
+	bsf		divemode					;     - set dive mode flag
+	bsf		count_divetime				;     - count dive time
+	return								;     - done
+set_dive_modes_shallow:
+	bcf		count_divetime				; NO  - stop counting dive time
+	btfss	divetime_longer_1min		;     - dive lasted longer than one minute?
+	bcf		divemode					;       NO  - quit dive mode as this was no real dive
+	return								;       done
+set_powersafe:
+	movlw	color_code_battery_low+.1	; get battery low level threshold [%]
+	cpfslt	batt_percent				; current battery level > low level threshold ?
+	return								; YES - ok, done
+	movlw	d'7'						; NO  - set type of alarm = battery low
+	movwf	alarm_type					;     - copy to alarm register
+	bsf		event_occured				;     - set event flag
+	movlw	.0							;     - coding of brightness level ECO
+	movff	WREG,opt_brightness			;     - set brightness to ECO
+	return								;     - done
+clear_resettable_average_depth:
+	; prime the resettable average depth with 0
+	CLRI	pressure_rel_avg_trip
+	bra		reset_resettable_average_depth1
+reset_resettable_average_depth:
+	; clear reset-average request
+	bcf		request_reset_avg
+	; prime the resettable average depth with the current relative pressure (depth)
+	MOVII	pressure_rel_cur_cached,pressure_rel_avg_trip
+reset_resettable_average_depth1:
+	; clear the resettable depth accumulator
+	clrf	pressure_rel_accu_trip+0
+	clrf	pressure_rel_accu_trip+1
+	clrf	pressure_rel_accu_trip+2
+	clrf	pressure_rel_accu_trip+3
+	; clear the resettable time accumulator
+	CLRI	divesecs_avg_trip
 	return
-set_dive_modes2:
-	bcf		divemode2					; stop time
+calc_average_depth:
-	btfss	realdive					; dive longer then one minute?
+	; 1. compute pressure_rel_cur_cached x 2, because this routine is called every 2nd second only
-	bcf		divemode					; NO  - this was no real dive
-	return								; YES - return
+	; copy current rel pressure to xB
+	MOVII	pressure_rel_cur_cached,xB
-set_dive_modes3:						; high-altitude mode
-	btfsc	realdive					; dive longer then one minute?
+	; multiply rel pressure x 2 (via shift left)
-	bra		set_dive_modes0				; YES - this is a real dive -> Use start_dive_threshold or ascend
+	bcf		STATUS,C
+	rlcf	xB+0,F
-	movlw	LOW  high_altitude_dive_threshold
+	rlcf	xB+1,F
-	movwf	sub_a+0
-	movlw	HIGH high_altitude_dive_threshold
+	; 2a add (pressure_rel_cur_cached x 2) to the resettable depth accumulator
-	movwf	sub_a+1
+	;    will work up to 9999 mbar * 60 * 60 * 24 = 863913600 mbar (24h @ 90 m depth)
-	bra		set_dive_modes1
+	movf	xB+0,W
+	addwf	pressure_rel_accu_trip+0,F
-set_powersafe:
+	movf	xB+1,W
-	movlw	color_code_battery_low+1; [%]
+	addwfc	pressure_rel_accu_trip+1,F
-	cpfslt	batt_percent
-	return
-	movlw	d'7'						; type of alarm (battery Low)
-	movwf	AlarmType					; copy to alarm register
-	bsf		event_occured				; set event flag
 	movlw	.0
-	movff	WREG,opt_brightness			; set brightness to ECO
+	addwfc	pressure_rel_accu_trip+2,F
-	return								; return
+	addwfc	pressure_rel_accu_trip+3,F
+	; 2b add (pressure_rel_cur_cached x 2) to the total depth accumulator
-reset_average:
+	;    will work up to 9999 mbar * 60 * 60 * 24 = 863913600 mbar (24h @ 90 m depth)
-	bcf		reset_average_depth			; clear reset-average flag
-	clrf	average_depth_hold+0		; clear the depth accumulator
-	clrf	average_depth_hold+1		; ...
-	clrf	average_depth_hold+2		; ...
-	clrf	average_depth_hold+3		; ...
-	clrf	average_divesecs+0			; clear the time accumulator
-	clrf	average_divesecs+1			; ...
-	SAFE_2BYTE_COPY rel_pressure,avg_rel_pressure ; prime result with current rel.pressure/depth
-	return
-calc_average_depth:
-	; 1. compute rel_pressure x 2, because this routine is called every 2nd second only
-	SAFE_2BYTE_COPY rel_pressure,xB		; copy current rel pressure to xB
-	bcf		STATUS,C
-	rlcf	xB+0,F						; multiply rel pressure x 2 (via shift left)
-	rlcf	xB+1,F						; ...
-	; 2a add (rel_pressure x 2) to the resettable depth accumulator
 	movf	xB+0,W
-	addwf	average_depth_hold+0,F
+	addwf	pressure_rel_accu_total+0,F
 	movf	xB+1,W
-	addwfc	average_depth_hold+1,F
+	addwfc	pressure_rel_accu_total+1,F
 	movlw	.0
-	addwfc	average_depth_hold+2,F
+	addwfc	pressure_rel_accu_total+2,F
-	addwfc	average_depth_hold+3,F			; will work up to 9999 mbar * 60 * 60 * 24 = 863913600 mbar (24h @ 90 m depth)
+	addwfc	pressure_rel_accu_total+3,F
-	; 2b add (rel_pressure x 2) to the total depth accumulator
+	; 3a compute the resettable average depth
-	movf	xB+0,W
-	addwf	average_depth_hold_total+0,F
+	; get the accumulated depth
-	movf	xB+1,W
+	movff	pressure_rel_accu_trip+0,xC+0
-	addwfc	average_depth_hold_total+1,F
+	movff	pressure_rel_accu_trip+1,xC+1
-	movlw	.0
+	movff	pressure_rel_accu_trip+2,xC+2
-	addwfc	average_depth_hold_total+2,F
+	movff	pressure_rel_accu_trip+3,xC+3
-	addwfc	average_depth_hold_total+3,F	; will work up to 9999 mbar * 60 * 60 * 24 = 863913600 mbar (24h @ 90 m depth)
+	; get the accumulated time
-	; 3a compute avg_rel_pressure on base of average_divesecs:2
+	MOVII	divesecs_avg_trip,xB
-	movff	average_depth_hold+0,xC+0
-	movff	average_depth_hold+1,xC+1
+	; divide accumulated depth by accumulated time
-	movff	average_depth_hold+2,xC+2
-	movff	average_depth_hold+3,xC+3		; copy accumulated depth
-	movff	average_divesecs+0,xB+0
-	movff	average_divesecs+1,xB+1			; copy accumulated time
 	call	div32x16						; xC:4 / xB:2 = xC+3:xC+2 with xC+1:xC+0 as remainder
-	movff	xC+0,avg_rel_pressure+0
-	movff	xC+1,avg_rel_pressure+1			; store result
+	; store result
+	MOVII	xC,pressure_rel_avg_trip		; resettable average depth
-	btfss	divemode2						; displayed divetime is running?
+	btfss	count_divetime					; is dive time counted?
 	return									; NO (e.g. too shallow)
-	; 3b compute avg_rel_pressure_total on base of average_divesecs_total:2
+	; 3b compute the dive total average depth
-	movff	average_depth_hold_total+0,xC+0
-	movff	average_depth_hold_total+1,xC+1
+	; get accumulated depth
-	movff	average_depth_hold_total+2,xC+2
+	movff	pressure_rel_accu_total+0,xC+0
-	movff	average_depth_hold_total+3,xC+3	; copy accumulated depth
+	movff	pressure_rel_accu_total+1,xC+1
-	movff	average_divesecs_total+0,xB+0
+	movff	pressure_rel_accu_total+2,xC+2
-	movff	average_divesecs_total+1,xB+1	; copy accumulated time
+	movff	pressure_rel_accu_total+3,xC+3
-	call	div32x16						; xC:4 / xB:2 = xC+3:xC+2 with xC+1:xC+0 as remainder
-	movff	xC+0,avg_rel_pressure_total+0
+	; get accumulated time
-	movff	xC+1,avg_rel_pressure_total+1	; store result
+	MOVII	divesecs_avg_total,xB
-	btfsc	reset_average_depth				; reset the resettable average depth?
+	; divide accumulated depth by accumulated time
-	rcall	reset_average					; YES - reset the resettable average depth
+	call	div32x16						; xC:4 = xC:4 / xB:2 with xA as remainder
-	TSTOSS	opt_2ndDepthDisp				; drawing avg depth instead of max depth?
+	; store result
-	return									; NO  - done
+	MOVII	xC,pressure_rel_avg_total		; total dive average depth
-	bsf		FLAG_TFT_max_depth				; YES - flag to update display
-	return
+	btfsc	request_reset_avg				; shall reset the resettable average depth?
+	rcall	reset_resettable_average_depth	; YES - reset the resettable average depth
-test_switches_divemode:						; checks switches in divemode
+	TSTOSC	opt_2ndDepthDisp				; drawing average depth instead of max depth?
-	btfsc	divemode_menu					; divemode menu shown?
+	bsf		FLAG_TFT_depth_maximum			; YES - flag to update display
+	btfsc	FLAG_gauge_mode					; in gauge mode?
+	bsf		FLAG_TFT_depth_maximum			; YES - flag to update display (needed for alternative layout)
+	return									; done
+test_switches_divemode:						; checks switches in dive mode, called every second
+	btfsc	dive_main_menu					; dive mode menu shown?
 	bra		test_switches_divemode_menu		; YES - use menu processor
 	btfsc	switch_left						; NO  - left button pressed?
 	goto	menuview_toggle					;       YES - menu or simulator tasks; and return...
 	btfss	switch_right					;       NO  - right button pressed?
 	return									;             NO  - done
-	tstfsz	menupos2						;             YES - any option shown?
+	bcf		switch_right					;             YES - clear button event
-	bra		test_switches_divemode1			;                   YES - do option tasks
+	tstfsz	active_premenu					;                 - any pre-menu task selected?
-	bsf		toggle_customview				;                   NO  - toggle custom view
+	bra		test_switches_divemode1			;                   YES - do option or menu tasks
+	bsf		request_next_custview			;                   NO  - request next custom view
 	return									;                       - done
 test_switches_divemode_menu:
-	btfsc	switch_left
+	btfsc	switch_left						; left button pressed?
-	bra		test_switches_divemode_menu2	; move cursor
+	bra		test_switches_divemode_menu2	; YES - move cursor
-	btfsc	switch_right					; left button pressed?
+	btfsc	switch_right					; NO  - right button pressed?
-	bra		test_switches_divemode_menu3	; YES - enter submenu or do something
+	bra		test_switches_divemode_menu3	;       YES - enter sub-menu or do something
-	return									; NO  - done
+	btfss	update_menu						;       NO  - shall update the menu?
+	return									;             NO  - done
+	bcf		update_menu						;             YES - clear request
+	goto	menu_draw_lines_divemode		;                 - redraw the menu (to update color coding) and return
 test_switches_divemode_menu1:
-	clrf	menupos1
+	clrf	menu_pos_cur
 test_switches_divemode_menu2:
-	incf	menupos1,F
+	bcf		switch_left
-	incf	menupos4,W						; menupos4 + 1 -> WREG
+	incf	menu_pos_cur,F
-	cpfslt	menupos1						; > menupos4 (set in menu_processor.asm)?
+	incf	menu_pos_max,W					; menu_pos_max + 1 -> WREG
+	cpfslt	menu_pos_cur					; > menu_pos_max ?
 	bra		test_switches_divemode_menu1	; YES - set to 1
-	call	TFT_divemode_menu_cursor		; update the cursor
+	call	TFT_show_menu_cursor_divemode	; update the cursor
-	bcf		switch_left
+	movlw	divemode_timeout_mainmenu		; get timeout for main menu
-	movlw	divemode_menu_timeout			; reload timeout
+	call	reset_timeout_time				; reset timeout
-	movwf	timeout_counter2				; timeout for divemode menu
 	return
-test_switches_divemode_menu3:			; enter submenu or do something
+test_switches_divemode_menu3:				; enter sub-menu or do something
 	bcf		switch_right
-;	decf	menupos1,F					; menu_processor needs 0-5...
+;	decf	menu_pos_cur,F					; menu_processor needs 0-5...
-	goto	do_line_menu				; Warning! trashes STKPTR and returns to diveloop_loop4:
+	goto	do_line_menu					; Warning! trashes STKPTR and returns to diveloop_menu_exit
 test_switches_divemode1:
-	bcf		switch_right
+	movlw	divemode_timeout_premenu	; get timeout for pre-menu
-	movlw	divemode_menuview_timeout
+	call	reset_timeout_time			; reset timeout
-	movwf	timeout_counter2			; reload timeout
+	movff	active_premenu,WREG			; get number of active pre-menu
-	movff	menupos2,WREG				; menupos2 holds number of customview/divemode menu function
 	dcfsnz	WREG,F
 	bra		divemode_option_gaschange	; switch to the the "better gas" / "better diluent"
 	dcfsnz	WREG,F
-	bra		divemode_option0			; start/setup Divemode menu
+	bra		divemode_option0			; start/setup dive mode menu
 	dcfsnz	WREG,F
 	bra		divemode_option1			; quit simulation?
 	dcfsnz	WREG,F
 	bra		divemode_option2			; descent 1m
 	dcfsnz	WREG,F
-	bra		divemode_option3			; ascend 1m
+	bra		divemode_option3			; ascend  1m
 	dcfsnz	WREG,F
-	bra		divemode_option4			; quit Apnoe mode
+	bra		divemode_option4			; quit apnoe mode
 	dcfsnz	WREG,F
 	bra		divemode_option5			; reset stopwatch (gauge mode only)
 	dcfsnz	WREG,F
-	bra		divemode_option6			; +5mins simulation
+	bra		divemode_option6			; +5 min simulation
 	dcfsnz	WREG,F
+IFDEF _compass
 	bra		divemode_option7			; store heading
+ELSE
+	return								; should never happen without compass
+ENDIF
 	dcfsnz	WREG,F
-	bra		divemode_option8			; switch to alternative layout
+	bra		divemode_option8			; switch layout
 	return
 gas_switched_common:
-	bcf		divemode_gaschange			; clear flag
+	bcf		request_gaschange			; clear request flag
-	btfss	FLAG_back_to_loop			; check if it is a switchback from OC bailout to loop
+IFDEF _ccr_pscr
+	btfss	request_back_to_loop		; is a switchback from OC bailout to loop requested?
 	bra		gas_switched_common0		; NO  - continue with checking if selected gas is valid
-	bcf		FLAG_back_to_loop			; YES - clear flag
+	bcf		request_back_to_loop		; YES - clear flag
-	movff	active_dil,menupos1			;       reload last diluent
+	movff	active_dil,menu_pos_cur		;     - reload last diluent
-	bra		gas_switched_common1		;       continue with common part
+	bra		gas_switched_common1		;     - continue with common part
+ENDIF
 gas_switched_common0:
-	tstfsz	menupos1					; menupos1 = 0 ?
+	tstfsz	menu_pos_cur				; menu_pos_cur = 0 ?
 	bra		gas_switched_common1		; NO  - valid gas
 	return								; YES - something went wrong, invalid gas, abort
 gas_switched_common1:
-	movf	menupos1,W					; get selected gas into WREG (1-6)
+	movf	menu_pos_cur,W				; get selected gas into WREG (1-6)
+IFDEF _ccr_pscr
 	btfsc	FLAG_oc_mode				; in OC mode?
 	bra		gas_switched_common_OC		; YES
-	btfsc	FLAG_bailout_mode			; in bailout?
+	btfsc	bailout_mode				; in bailout?
 	bra		gas_switched_common_OC		; YES
 gas_switched_common_loop:				; NO to both - must be loop mode then
 	rcall	setup_dil_registers			; with WREG = diluent 1-6
 	rcall	deco_setup_cc_diluents		; with WREG = diluent 1-6
 	bra		gas_switched_common3
+ENDIF
 gas_switched_common_OC:
 	rcall	setup_gas_registers			; with WREG = Gas 1-6
 	rcall	deco_setup_oc_gases			; with WREG = Gas 1-6
 gas_switched_common3:
 	banksel	int_O_breathed_ppO2
 	bcf		int_O_breathed_ppO2+1,int_warning_flag		; | color that belonged to the previous gas
 	banksel	common
 	bsf		FLAG_TFT_active_gas_divemode				; redraw gas/setpoint/diluent
 	call	restart_deco_engine_wo_ceiling				; abort any running deco calculations and restart the deco engine
 	; set flags for profile recording
-	bsf		event_occured				; set event flag
+	bsf		event_occured				; set global event flag
-	btfsc	FLAG_bailout_mode			; choose OC Bailouts (OC Gases)
+IFDEF _ccr_pscr
-	bsf		bailoutgas_event			; bailout gas change
+	btfsc	bailout_mode				; in bailout mode?
-	btfss	FLAG_bailout_mode			; choose OC Bailouts (OC Gases)
+	bsf		event_bailout				; YES - set gas change event due to bailout
-	bsf		stored_gas_changed			; OC gas change
+	btfss	bailout_mode				; in bailout mode?
+ENDIF
+	bsf		event_gas_change			; NO  - set gas change event (normal change)
 	return
 ; Code to pass all parameters to the C code
 	global	get_first_gas_to_WREG
 get_first_gas_to_WREG:					; gets first gas (1-5) into WREG
-	lfsr	FSR1,opt_gas_type			; point to gas types
+	lfsr	FSR1,opt_gas_type			; load base address of the gas types
 	clrf	lo							; start with gas 0
 get_first_gas_to_WREG2:
-	movf	lo,W
+	movf	lo,W						; set index
-	movf	PLUSW1,W					; get type of gas #lo (0=Disabled, 1=First, 2=Travel, 3=Deco)
+	movf	PLUSW1,W					; get type of gas (0=Disabled, 1=First, 2=Travel, 3=Deco)
-	sublw	.1							; it is = 1 (First Gas)
+	sublw	.1							; is it of type First?
-	bz		get_first_gas_to_WREG3		; found the first gas!
+	bz		get_first_gas_to_WREG3		; YES - found the First gas
-	incf	lo,F						; ++
+	incf	lo,F						; NO  - increment index
-	movlw	NUM_GAS+1
+	movlw	NUM_GAS+1					;     - get highest index+1
-	cpfseq	lo							; all done?
+	cpfseq	lo							;     - all gases checked?
-	bra		get_first_gas_to_WREG2		; NO - not yet
+	bra		get_first_gas_to_WREG2		;       NO  - not yet
-	; no first gas found, use #1
+	movlw	.1							;       YES - return gas 1
-	movlw	.1							; coding of First gas
+	movff	WREG,opt_gas_type+0			;           - set to type First
-	movff	WREG,opt_gas_type+0			; set gas 1 to First
+	return								;           - done
-	return
 get_first_gas_to_WREG3:
-	movf	lo,W						; put into WREG
+	movf	lo,W						; copy index of gas found to be the First to WREG
-	incf	WREG,W						; 0-4 -> 1-5
+	incf	WREG,W						; turn index into gas number (0-4 -> 1-5)
 	return								; done
+;=============================================================================
+IFDEF _ccr_pscr
 	global	get_first_dil_to_WREG
 get_first_dil_to_WREG:					; gets first dil (1-5) into WREG
-	lfsr	FSR1,opt_dil_type			; point to dil types
+	lfsr	FSR1,opt_dil_type			; load base address of the dil types
 	clrf	lo							; start with dil 0
 get_first_dil_to_WREG2:
-	movf	lo,W
+	movf	lo,W						; set index
-	movf	PLUSW1,W					; get type of Dil #lo  (0=Disabled, 1=First, 2=Normal)
+	movf	PLUSW1,W					; get type of Dil (0=Disabled, 1=First, 2=Normal)
-	sublw	.1							; it is = 1 (First Dil)
+	sublw	.1							; is it of type First?
-	bz		get_first_dil_to_WREG3		; found the first dil!
+	bz		get_first_dil_to_WREG3		; YES - found the First dil
-	incf	lo,F						; ++
+	incf	lo,F						; NO  - increment index
-	movlw	NUM_GAS+1
+	movlw	NUM_GAS+1					;     - get highest index+1
-	cpfseq	lo							; all done?
+	cpfseq	lo							;     - dils checked?
-	bra		get_first_dil_to_WREG2		; NO - not yet
+	bra		get_first_dil_to_WREG2		;       NO  - not yet
-	; no first dil found, use #1
+	movlw	.1							;       YES - return dil 1
-	movlw	.1							; coding of First Dil
+	movff	WREG,opt_dil_type+0			;           - set to type First
-	movff	WREG,opt_dil_type+0			; set dil 1 to First
+	return								;           - done
-	return
 get_first_dil_to_WREG3:
-	movf	lo,W						; Put into WREG
+	movf	lo,W						; copy index of dil found to be the First to WREG
-	incf	WREG,W						; 0-4 -> 1-5
+	incf	WREG,W						; turn index into dil number (0-4 -> 1-5)
 	return								; done
+ENDIF
+;=============================================================================
 deco_setup_oc_gases:					; with currently breathed gas in WREG (1-5 or 6)
 	movff	char_O_deco_status,lo		; working copy of char_O_deco_status in bank common
 deco_setup_oc_gases_pre:				; entry point with lo preloaded
-	movff	WREG,char_I_current_gas		; set gas to start with when doing the deco calculations
+	movff	WREG,char_I_current_gas_num	; set gas to start with when doing the deco calculations
 	;
 	; Memory Map:
 	; ---------------------------------------------------------------------------------
 	; opt_gas_O2_ratio		res NUM_GAS		|	char_I_deco_O2_ratio		res NUM_GAS
 	; opt_dil_O2_ratio		res NUM_GAS		|
 	; opt_gas_type			res NUM_GAS		|	char_I_deco_gas_type		res NUM_GAS
 	; opt_dil_type			res NUM_GAS		|
 	; opt_gas_change		res NUM_GAS		|	char_I_deco_gas_change		res NUM_GAS
 	; opt_dil_change		res NUM_GAS		|
 	;
-	lfsr	FSR2,char_I_deco_O2_ratio	; Load FSR2 with base address of char_I_deco_O2_ratio.
+	lfsr	FSR2,char_I_deco_O2_ratio	; load FSR2 with base address of char_I_deco_O2_ratio.
 										; FSR2 will step through all char_I_deco_... vars.
 	lfsr	FSR1,opt_gas_O2_ratio		; load FSR1 with base address of opt_gas_O2_ratio
 	rcall	deco_setup_copy				; copy all OC O2 ratios
 	lfsr	FSR1,opt_gas_He_ratio		; load FSR1 with base address of opt_gas_He_ratio
 	rcall	deco_setup_copy				; copy all OC He ratios
 	bcf		lo,DECO_MODE_PSCR_FLAG		; clear the pSCR-mode flag (may not be set, but never mind)
 	bcf		lo,DECO_MODE_LOOP_FLAG		; clear the loop/CCR-mode flag
 	movff	lo,char_O_deco_status		; bank safe write-back of char_O_deco_status
 	return
+;=============================================================================
+IFDEF _ccr_pscr
 deco_setup_cc_diluents:					; with currently breathed diluent in WREG (1-5 or 6)
 	movff	char_O_deco_status,lo		; working copy of char_O_deco_status in bank common
 deco_setup_cc_diluents_pre:				; entry point with lo preloaded
-	btfsc	FLAG_bailout_mode			; check if in bailout condition       | --------------- FOR SAFETY ONLY --------------
+	btfsc	bailout_mode				; check if in bailout condition       | --------------- FOR SAFETY ONLY --------------
 	bra		deco_setup_oc_gases_pre		; YES - revert to setting up OC gases | This branch should never happen to be taken...
-	movff	WREG,char_I_current_gas		; NO  - set diluent to start with when doing the deco calculations
+	movff	WREG,char_I_current_gas_num	; NO  - set diluent to start with when doing the deco calculations
 	;
 	; Memory Map:
 	; ---------------------------------------------------------------------------------
 	; opt_gas_O2_ratio		res NUM_GAS		|
 	; opt_dil_O2_ratio		res NUM_GAS		|	char_I_deco_O2_ratio		res NUM_GAS
 	; opt_gas_type			res NUM_GAS		|
 	; opt_dil_type			res NUM_GAS		|	char_I_deco_gas_type		res NUM_GAS
 	; opt_gas_change		res NUM_GAS		|
 	; opt_dil_change		res NUM_GAS		|	char_I_deco_gas_change		res NUM_GAS
 	;
-	lfsr	FSR2,char_I_deco_O2_ratio	; Load FSR2 with base address of char_I_deco_O2_ratio.
+	lfsr	FSR2,char_I_deco_O2_ratio	; load FSR2 with base address of char_I_deco_O2_ratio.
 										; FSR2 will step through all char_I_deco_... vars.
 	lfsr	FSR1,opt_dil_O2_ratio		; load FSR1 with base address of opt_dil_O2_ratio
 	rcall	deco_setup_copy				; copy all dil O2 ratios
 	lfsr	FSR1,opt_dil_He_ratio		; load FSR1 with base address of opt_dil_He_ratio
 	rcall	deco_setup_copy				; copy all dil He ratios
 	btfsc	FLAG_pscr_mode				; check if we are in pSCR mode
 	bsf		lo,DECO_MODE_PSCR_FLAG		; YES - set additional flag for pSCR mode
 	movff	lo,char_O_deco_status		; bank safe write-back of char_O_deco_status
 	return
+ENDIF
+;=============================================================================
 deco_setup_copy:
 	movlw	NUM_GAS						; load loop counter with number of gases (5)
 deco_setup_copy_loop:
 	movff	POSTINC1,POSTINC2			; copy from (FSR1) to (FSR2)
 	decfsz	WREG						; decrement loop counter and check if it became 0
 	bra		deco_setup_copy_loop		; NO  - not yet, loop
 	return								; YES - done
-	global	setup_gas_registers
 setup_gas_registers:					; with currently breathed gas in WREG (1-5 or 6)
 	movwf	active_gas					; set as current gas
 	movlw	.6
 	cpfseq	active_gas					; gas = gas6 ?
 	bra		setup_gas_registers_15		; NO - load gas 1-5
 	movff	gas6_O2_ratio,char_I_O2_ratio ; copy gas6 O2 ratio to deco engine
+IFDEF _helium
 	movff	gas6_He_ratio,char_I_He_ratio ; copy gas6 H2 ratio to deco engine
+ENDIF
 	movlw	.3							; declare gas6 as a deco gas
 	movff	WREG,char_I_current_gas_type; copy gas type to deco engine
-	movff	curr_depth,char_I_gas6_depth; set current depth as change depth
+	movff	depth_meter,char_I_gas6_depth;set current depth as change depth
 	bra		setup_gas_registers_com		; continue with common part
 setup_gas_registers_15:
-	decf	active_gas,W				; 1-5 -> 0-4
+	lfsr	FSR1,opt_gas_O2_ratio		; load base address of gas data
-	lfsr	FSR1,opt_gas_O2_ratio
+	decf	active_gas,W				; set index to O2 ratio of current gas (1-5 -> 0-4)
 	movff	PLUSW1,char_I_O2_ratio		; copy gas 1-5 O2 ratio to deco engine
-	lfsr	FSR1,opt_gas_He_ratio
+	addlw	.10							; advance index from O2 ratio to He ratio
+IFDEF _helium
 	movff	PLUSW1,char_I_He_ratio		; copy gas 1-5 He ratio to deco engine
-	lfsr	FSR1,opt_gas_type			;
+ENDIF
+	addlw	.10							; advance index from He ratio to gas type
 	movff	PLUSW1,char_I_current_gas_type ; copy gas 1-5 type (0=Disabled, 1=First, 2=Travel, 3=Deco)
 setup_gas_registers_com:
 	movff	char_O_main_status,lo		; working copy of char_O_main_status in bank common
 	bcf		lo,DECO_MODE_PSCR_FLAG		; clear the pSCR-mode flag (may not be set, but never mind)
 	bcf		lo,DECO_MODE_LOOP_FLAG		; clear the loop/CCR-mode flag
 	movff	lo,char_O_main_status		; bank safe write-back of char_O_main_status
 	movf	active_gas,W				; reload WREG with gas 1-5 or 6 (important!)
 	return
-	global	setup_dil_registers
+;=============================================================================
+IFDEF _ccr_pscr
 setup_dil_registers:					; with currently breathed gas in WREG (1-5 or 6)
-	btfsc	FLAG_bailout_mode			; check if in bailout condition                      | --------------- FOR SAFETY ONLY --------------
+	btfsc	bailout_mode				; check if in bailout condition                      | --------------- FOR SAFETY ONLY --------------
 	bra		setup_gas_registers			; revert to setting up OC gases in bailout condition | This branch should never happen to be taken...
 	movwf	active_dil					; set as current diluent
 	movlw	.6
 	cpfseq	active_dil					; diluent = gas6 ?
 	bra		setup_dil_registers_15		; NO - load diluent 1-5
 	movff	gas6_O2_ratio,char_I_O2_ratio ; copy gas6 O2 ratio to deco engine
+IFDEF _helium
 	movff	gas6_He_ratio,char_I_He_ratio ; copy gas6 H2 ratio to deco engine
+ENDIF
 	movlw	.2							; declare gas6 as a normal diluent
 	movff	WREG,char_I_current_gas_type; copy gas type to deco engine
-	movff	curr_depth,char_I_gas6_depth; set current depth as change depth
+	movff	depth_meter,char_I_gas6_depth;set current depth as change depth
 	bra		setup_dil_registers_com		; continue with common part
 setup_dil_registers_15:
-	decf	active_dil,W				; 1-5 -> 0-4
+	lfsr	FSR1,opt_dil_O2_ratio		; load base address of diluent data
-	lfsr	FSR1,opt_dil_O2_ratio
+	decf	active_dil,W				; set index to O2 ratio of current diluent (1-5 -> 0-4)
 	movff	PLUSW1,char_I_O2_ratio		; copy diluent 1-5 O2 ratio to deco engine
-	lfsr	FSR1,opt_dil_He_ratio
+	addlw	.10							; advance index from O2 ratio to He ratio
+IFDEF _helium
 	movff	PLUSW1,char_I_He_ratio		; copy diluent 1-5 He ratio to deco engine
-	lfsr	FSR1,opt_dil_type			;
+ENDIF
-	movff	PLUSW1,char_I_current_gas_type ; copy dil type (0=Disabled, 1=First, 2=Normal)
+	addlw	.10							; advance index from He ratio to diluent type
+	movff	PLUSW1,char_I_current_gas_type ; copy diluent type (0=Disabled, 1=First, 2=Normal)
 setup_dil_registers_com:
 	movff	char_O_main_status,lo		; working copy of char_O_main_status in bank common
 	bsf		lo,DECO_MODE_LOOP_FLAG		; loop flag is set in both, CCR and pSCR mode
 	bcf		lo,DECO_MODE_PSCR_FLAG		; clear pSCR mode flag by default
 	btfsc	FLAG_pscr_mode				; check if we are in pSCR mode
 	bsf		lo,DECO_MODE_PSCR_FLAG		; YES - set additional flag for pSCR mode
 	movff	lo,char_O_main_status		; bank safe write-back of char_O_main_status
 	movf	active_dil,W				; reload WREG with diluent 1-5 or 6 (important!)
 	return
+ENDIF
+;=============================================================================
 divemode_option_gaschange:				; switch to the "better gas" / "better diluent"
+IFDEF _ccr_pscr
 	btfsc	FLAG_oc_mode				; in OC mode?
 	bra		divemode_option_gaschange_oc; YES
-	btfsc	FLAG_bailout_mode			; in bailout?
+	btfsc	bailout_mode				; in bailout?
 	bra		divemode_option_gaschange_oc; YES
 divemode_option_gaschange_loop:			; in CCR/pSCR mode and not in bailout
-	movff	best_dil_number,menupos1	; NO  - select best diluent
+	movff	best_dil_number,menu_pos_cur; NO  - select best diluent
 	bcf		better_dil_available		;     - clear flag immediately
 	bra		divemode_option_gaschange3	;     - continue with common part
+ENDIF
 divemode_option_gaschange_oc:			; in OC or bailout
-	movff	best_gas_number,menupos1	; select best gas
+	movff	best_gas_number,menu_pos_cur; select best gas
 	bcf		better_gas_available		; clear flag immediately
 divemode_option_gaschange3				; common part
-	bsf		divemode_gaschange			; command a gas/diluent change
+	bsf		request_gaschange			; request a gas/diluent change
-	call	menuview_toggle_reset		; terminate the options menu
+	call	menuview_toggle_reset		; terminate the pre-menu
 	return
+	global	divemode_option0_return
 divemode_option0:						; start/setup dive mode menu
 	call	TFT_clear_divemode_menu		; clear menu area
-	bcf		menuview
+	bcf		dive_options_menu			; dive options menu is not shown anymore
-	call	do_main_divemenu
+	call	do_main_divemenu			; hand over to menu processor
+divemode_option0_return:				; return point for menu processor
-	global	divemode_option0_return
+	call	TFT_show_menu_cursor_divemode ; show the cursor
-divemode_option0_return:
+	clrf	active_premenu				; set pre-menu    is not shown any more
-;	movlw	.1
+	bcf		safety_stop_active			; set safety stop is not shown any more
-;	movwf	menupos1					; set to first option in dive mode menu
+	bsf		dive_main_menu				; set main menu   is     shown now
-	call	TFT_divemode_menu_cursor	; show the cursor
+	movlw	divemode_timeout_mainmenu	; get timeout for main menu
-	movlw	divemode_menu_timeout
+	call	reset_timeout_time			; reload timeout
-	movwf	timeout_counter2			; timeout for dive mode menu
+	goto	diveloop_menu_exit			; go back to dive loop (menu processor resets STKPTR!)
-	bsf		divemode_menu				; set flag
-	clrf	menupos2					; clear option counter
-	goto	diveloop_loop4				; go back to dive loop (menu processor trashes STKPTR!)
-divemode_option4:
-	movlw	d'58'						; two seconds left
-	movwf	timeout_counter1+0
-	movlw	apnoe_timeout-1				; apnoe timeout [min]
-	movwf	apnoe_timeout_counter
-	btfss	simulatormode_active		; in simulator mode?
-	return								; NO
-	;bra	divemode_option1			; YES
 divemode_option1:						; quit simulation mode
-	banksel	isr_backup
+	clrf	simulatormode_depth			; set target depth to zero
-	movlw	LOW  .1000
+	bsf		quit_simulatormode			; request ISR to end simulator mode
-	movwf	sim_pressure+0
+	call	menuview_toggle_reset		; terminate the pre-menu
-	movlw	HIGH .1000
+	btfsc	FLAG_apnoe_mode				; in apnoe mode?
-	movwf	sim_pressure+1				; set to 0m -> end of dive
+	bcf		divemode					; YES - force end of dive mode
-	banksel	common
+	return								; done
-	call	menuview_toggle_reset		; reset to zero (zero = no menu view)
+divemode_option2:						; plus 1 meter
-	btfss	FLAG_apnoe_mode				; in apnoe mode?
+	movlw	ostc_depth_max-1			; load depth limit into WREG
-	return								; NO - done
+	cpfsgt	simulatormode_depth			; simulated depth <= limit ?
-	movlw	d'58'						; two seconds left
+	incf	simulatormode_depth,F		; YES - increment simulated depth
-	movwf	timeout_counter1+0
+	return								; done
-	movlw	apnoe_timeout-1				; apnoe timeout [min]
-	movwf	apnoe_timeout_counter
+divemode_option3:						; minus 1 meter
-	return
+	tstfsz	simulatormode_depth			; simulated depth > 0 ?
+	decf	simulatormode_depth,F		; YES - decrement simulated depth
-divemode_option3:						; minus 1m
+	return								; done
-	banksel	isr_backup
-	movlw	d'100'
+divemode_option4:						; quit apnoe mode (available while at the surface only)
-	subwf	sim_pressure+0
+	btfsc	sensor_override_active		; in simulator mode?
-	movlw	.0
+	bra		divemode_option1			; YES - use simulator quit procedure
-	subwfb	sim_pressure+1
+	bcf		divemode					; NO  - force end of dive mode
-	rcall	divemode_simulator_check_limits
+	return								;     - done
-	banksel	common
-	return
-divemode_option2:						; plus 1m
-	banksel	isr_backup
-	movlw	d'100'
-	addwf	sim_pressure+0,F
-	movlw	.0
-	addwfc	sim_pressure+1,F
-	rcall	divemode_simulator_check_limits
-	banksel	common
-	return
 divemode_option5:
-	call	menuview_toggle_reset		; reset to zero (zero = no menu view)
+	bsf		request_reset_avg			; request reset of average depth
-	bsf		reset_average_depth			; set flag
+	goto	menuview_toggle_reset		; terminate pre-menu and return
-	return
 divemode_option6:
-	; advance tissues and deco by 5 minutes
+	; advance tissues pressures and deco obligation by 5 minutes
 	movlw	.5							; + 5 minutes
 	movff	WREG,char_I_sim_advance_time; copy to mailbox
-	call	restart_deco_engine
+	call	restart_deco_engine			; condition deco engine to execute the +5 minutes
-	; stop divetime incrementing in ISR
+	; stop dive time incrementing in ISR
-	bcf		divemode2
+	bcf		count_divetime
-	; add 5 minutes to divemins
+	; add 5 minutes to counted_divetime_mins
-	movlw	.5
+	ADDLI	.5,counted_divetime_mins
-	addwf	divemins+0,F
-	movlw	.0
+	; add 5 minutes (300 seconds) to total_divetime_secs
-	addwfc	divemins+1,F
+	ADDLI	.300,total_divetime_secs
-	; add 5 minutes (5 * 60 seconds) to total_divetime_seconds
-	movlw	LOW  (.5*.60)
-	addwf	total_divetime_seconds+0,F
-	movlw	HIGH (.5*.60)
-	addwfc	total_divetime_seconds+1,F
 	; continue dive time incrementing in ISR
-	bsf		divemode2
+	bsf		count_divetime
-	; add 5 minutes (5 * 60 seconds) to resettable time accumulator
+	; add 5 minutes (300 seconds) to resettable time accumulator
-	movlw	LOW  (.5*.60)
+	ADDLI	.300,divesecs_avg_trip
-	addwf	average_divesecs+0,F
-	movlw	HIGH (.5*.60)
+	; add 5 minutes (300 seconds) to total time accumulator
-	addwfc	average_divesecs+1,F
+	ADDLI	.300,divesecs_avg_total
-	; add 5 minutes (5 * 60 seconds) to total time accumulator
-	movlw	LOW  (.5*.60)
-	addwf	average_divesecs_total+0,F
-	movlw	HIGH (.5*.60)
-	addwfc	average_divesecs_total+1,F
 	; calculate 300 x depth in mbar (300 = 5 min * 60 sec/min)
-	SAFE_2BYTE_COPY rel_pressure, xB
+	MOVII	pressure_rel_cur_cached,xB
-	movlw	LOW  (.5*.60)
+	MOVLI	.300,xA
-	movwf	xA+0
+	call	mult16x16					; xC = xA * xB
-	movlw	HIGH (.5*.60)
-	movwf	xA+1
-	call	mult16x16					; xA*xB=xC
 	; add to the resettable depth accumulator
 	movf	xC+0,W
-	addwf	average_depth_hold+0,F
+	addwf	pressure_rel_accu_trip+0,F
 	movf	xC+1,W
-	addwfc	average_depth_hold+1,F
+	addwfc	pressure_rel_accu_trip+1,F
 	movf	xC+2,W
-	addwfc	average_depth_hold+2,F
+	addwfc	pressure_rel_accu_trip+2,F
 	movf	xC+3,W
-	addwfc	average_depth_hold+3,F
+	addwfc	pressure_rel_accu_trip+3,F
 	; add to the total depth accumulator
 	movf	xC+0,w
-	addwf	average_depth_hold_total+0,F
+	addwf	pressure_rel_accu_total+0,F
 	movf	xC+1,w
-	addwfc	average_depth_hold_total+1,F
+	addwfc	pressure_rel_accu_total+1,F
 	movf	xC+2,w
-	addwfc	average_depth_hold_total+2,F
+	addwfc	pressure_rel_accu_total+2,F
 	movf	xC+3,w
-	addwfc	average_depth_hold_total+3,F
+	addwfc	pressure_rel_accu_total+3,F
 IFDEF _cave_mode
 	; update backtracking data
-	movlw	.5							; add backtrack data for 5 minutes
+	movlw	.5							; configure 5 minutes
-	call	update_backtrack			; make it so
+	call	update_backtrack			; add backtrack data for 5 minutes
 ENDIF
-	goto	menuview_toggle_reset		; and return...
+	goto	menuview_toggle_reset		; terminate the pre-menu and return
+IFDEF _compass
 divemode_option7:
-	; Store heading for compass view
+	; store heading for compass view
-	movff	compass_heading_shown+0,compass_bearing+0
+	MOVII	compass_heading_shown,compass_bearing
-	movff	compass_heading_shown+1,compass_bearing+1
+	bsf		compass_bearing_set			; set flag to show heading
-	bsf		compass_bearing_set			; set flag
+	goto	menuview_toggle_reset		; terminate the pre-menu and return
-	goto	menuview_toggle_reset		; and return...
+ENDIF
 divemode_option8:
-	bsf		alternative_divelayout		; set flag for alternative layout mode
 	call	menuview_toggle_reset		; terminate the pre-menu
 	call	TFT_ClearScreen				; clear the whole screen
-	bsf		FLAG_TFT_divemode_mask_alt	; set flag to draw the alternative mask
+	btg		alt_layout_active			; toggle layout
-	movff	menupos3,customview_divemode; back-up the custom view shown in normal layout
-	clrf	menupos3					; select the default alternative layout
+	bcf		depth_warn_att_last			; set warning or attention on the depth   not shown
-	call	customview_mask_alternative ; draw   the default alternative layout
+	bcf		depth_inverse_last			; set depth displayed in inverse as       not shown
-	return								; done
+	bcf		sign_shown					; set warning/attention/advice sign       not shown
+	bcf		velocity_active_num			; set numerical vertical velocity display not shown
+	bcf		velocity_active_vsi			; set vertical  vertical velocity display not shown
-divemode_simulator_check_limits:
+	bcf		safety_stop_active			; set safety stop                         not shown
-	; check limits (150m and 0m)
-	movlw	LOW  d'16000'				; compare to 16 bar = 16000 mbar (150m)
+	bsf		FLAG_TFT_divemode_mask		; request redraw of dive screen mask
-	subwf	sim_pressure+0,W
+	bsf		FLAG_TFT_divetime			; request redraw of dive time
-	movlw	HIGH d'16000'
+	bsf		FLAG_TFT_depth_current		; request redraw of current depth
-	subwfb	sim_pressure+1,W
+	bsf		FLAG_TFT_depth_maximum		; request redraw of maximum depth
-	bnc		divemode_simulator_check_limits2 ; no carry = borrow = not deeper
+	bsf		FLAG_TFT_active_gas_divemode; request redraw of gas and setpoint
+	bsf		FLAG_TFT_customview_mask	; request redraw of custom view mask
-	; too deep, limit to 150m
+	bsf		FLAG_TFT_temperature		; request redraw of temperature
-	movlw	LOW  d'16000'
-	movwf	sim_pressure+0
+	goto	request_redraw_NDL_deco_data; request redraw of NDL/deco data and return
-	movlw	HIGH d'16000'
-	movwf	sim_pressure+1
-	return
-divemode_simulator_check_limits2:
-	movlw	LOW  d'1000'				; compare to 1 bar == 0m == 1000 mbar
-	subwf	sim_pressure+0,W
-	movlw	HIGH d'1000'
-	subwfb	sim_pressure+1,W
-	btfsc	STATUS,C					; no carry = borrow = not deeper
-	return								; deeper than 0 m == ok
-	; too shallow, limit to 0m
-	movlw	LOW  d'1000'
-	movwf	sim_pressure+0
-	movlw	HIGH d'1000'
-	movwf	sim_pressure+1
-	return
 ;=============================================================================
 ; Find the best gas and diluent for the current depth
 ; and check if a gas/diluent change is to be advised.
 ;
 ;
 ; in OC mode          : - checks only gases for best gas
 ;                       - sets better_gas_available on OC gases
 ;
 check_gas_best:
-	movff	amb_press_10+0,xA+0				; copy ambient pressure / 10 into xA:2, will be used by ppO2 min/max checks later
+	btfsc	FLAG_gauge_mode					; in gauge mode?
-	movff	amb_press_10+1,xA+1				; ...
+	return									; YES - done
-	; set maximum ppO2 allowed
-	movff	char_I_ppO2_max,ppO2_max		; max ppO2 for working phase (default)
+	MOVII	pressure_abs_10,xA				; copy absolute pressure / 10 into xA:2, will be used by ppO2 min/max checks later
+	; compute max. allowed deco ppO2
+	movff	char_I_ppO2_max_deco,WREG		; max ppO2 [cbar] for deco phase
+	mullw	.100							; compute max ppO2 * 100, result is in 0.1 mbar
+	ADDLI	ppO2_margin_on_max,PROD			; add ppO2 margin on max value to compensate for surface pressures > 1000 hPa
+	MOVII	PROD,ppO2_max_deco				; store as deco ppO2 max
+	; compute max. allowed default ppO2
 	movff	char_O_deco_info,lo				; bank-safe copy of deco info vector
-	btfsc	lo,deco_flag					; is the ppo2 deco limit enabled?
+	btfss	lo,deco_flag					; is the ppO2 deco limit enabled?
-	movff	char_I_ppO2_max_deco,ppO2_max	; YES - replace by max ppO2 for deco phase
+	bra		check_gas_best_1				; NO  - compute default ppO2 max
+	MOVII	ppO2_max_deco,ppO2_max_default	; YES - copy default ppO2 max from deco max.
+	bra		check_gas_best_2				;     - continue with common part
+check_gas_best_1:
+	movff	char_I_ppO2_max_work,WREG		; max ppO2 [cbar] for working phase
+	mullw	.100							; compute max ppO2 * 100, result is in 0.1 mbar
+	ADDLI	ppO2_margin_on_max,PROD			; add ppO2 margin on max value to compensate for surface pressures > 1000 hPa
+	MOVII	PROD,ppO2_max_default			; store as default ppO2 max
+check_gas_best_2:
+IFDEF _ccr_pscr
 	; check dive mode
 	btfsc	FLAG_oc_mode					; in OC mode?
 	bra		check_gas_best_gas				; YES - skip diluents, check for best gas only
 check_gas_best_dil:
 	; set minimum ppO2 required
 	movff	char_I_ppO2_min,WREG			; min ppO2 for pure diluent in CCR mode (default)
 	btfsc	FLAG_pscr_mode					; in pSCR mode?
-	movff	char_I_ppO2_min_loop,ppO2_min	; YES - replace by min ppO2 for pure diluent in pSCR mode
+	movff	char_I_ppO2_min_loop,WREG		; YES - replace by min ppO2 for pure diluent in pSCR mode
+	mullw	.100							; min ppO2 * 100, result in 0.1 mbar
+	MOVII	PROD,ppO2_min					; store in ppO2_min
 	; preset results to nothing found
 	clrf	best_gas_num					; initialize best diluent as 0 = nothing found yet
-	bcf		better_dil_available			; =1: a better diluent is available and a gas change is advised in divemode
+	bcf		better_dil_available			; =1: a better diluent is available and a gas change is advised in dive mode
 ;	; current diluent = 'gas6' ?
 ;	movlw	.6								;
 ;	cpfseq	active_dil						; using 'gas6' as current diluent?
 ;	bra		check_gas_best_dil0				; NO  - continue
 ;	bra		check_gas_best_dil3				; YES - suppress better diluent search in this case
 ;	bra		check_gas_best_dil_loop
 ;
 	; store result
 	movff	best_gas_num,best_dil_number	; store new best diluent found (1-5 or 0 of no usable diluent available)
 	; check if change advices shall be given in general
-	btfsc	FLAG_bailout_mode				; in bailout?
+	btfsc	bailout_mode					; in bailout?
 	bra		check_gas_best_gas				; YES - no better diluent advice when in bailout
 check_gas_best_dil1:
 	; check if a change advice shall be given right now
 	movf	best_dil_number,W				; load number of best diluent into WREG (1-5)
 	bz		check_gas_best_dil3				; has a best diluent been found at all?  NO - nothing to signal for
 	cpfseq	active_dil						; is this the currently used diluent?
 	bra		check_gas_best_dil2				; NO
 	bra		check_gas_best_dil3				; YES - no need to signal a better diluent if this diluent is already in use
 check_gas_best_dil2:
-	btfsc	setpoint_fallback				; is a fallback warning active?
+	btfsc	sp_fallback						; in fallback condition?
 	bra		check_gas_best_dil3				; YES - suppress better diluent prompt in this case
 	; not using the best gas - show better diluent hint whenever a better diluent is available
 	bsf		better_dil_available			; signal that a better diluent is available
 	bsf		FLAG_TFT_active_gas_divemode	; redraw gas/setpoint/diluent
 check_gas_best_dil3:
 	btfss	better_dil_available			; shall a better diluent be signaled for?
-	bcf		blinking_better_dil				; NO  - clear blinking flag
+	bcf		better_dil_blinking				; NO  - clear blinking flag
 	; continue with checking for best bailout gas
+ENDIF	; _ccr_pscr
 check_gas_best_gas:
 	; set minimum ppO2 required
-	movff	char_I_ppO2_min,ppO2_min		; min ppO2 for OC/Bailout
+	movff	char_I_ppO2_min,WREG			; min ppO2 for OC and Bailout
+	mullw	.100							; min ppO2 * 100, result in 0.1 mbar
+	MOVII	PROD,ppO2_min					; store in ppO2_min
 	; preset results to nothing found
 	clrf	best_gas_num					; initialize best gas as 0 = nothing found yet
-	bcf		better_gas_available			; =1: a better gas is available and a gas change is advised in divemode
+	bcf		better_gas_available			; =1: a better gas is available and a gas change is advised in dive mode
 ;	; current gas = 'gas6' ?
 ;	movlw	.6								;
 ;	cpfseq	active_gas						; using 'gas6' as current gas?
 ;	bra		check_gas_best_gas0				; NO  - continue
 ;	bra		check_gas_best_gas3				; YES - suppress better gas search in this case
 	; store result
 	movff	best_gas_num,best_gas_number	; store new best gas found (1-5 or 0 of no usable gas available)
 	; check if change advices shall be given in general
 	btfsc	FLAG_oc_mode					; in OC mode?
 	bra		check_gas_best_gas1				; YES
-	btfsc	FLAG_bailout_mode				; in bailout?
+	btfsc	bailout_mode					; in bailout?
 	bra		check_gas_best_gas1				; YES
 	return									; NO  - no better (OC) gas advice when not in OC or bailout mode
 check_gas_best_gas1:						; check if we are already on the best gas
 	; check if a change advice shall be given right now
 	movf	best_gas_number,W				; load number of best gas into WREG (1-5)
 	; not using the best gas - show better gas hint whenever a better gas is available
 	bsf		better_gas_available			; YES - signal that a better gas is available
 	bsf		FLAG_TFT_active_gas_divemode	; YES - redraw gas/setpoint/diluent
 check_gas_best_gas3:
 	btfss	better_gas_available			; shall a better gas be signaled for?
-	bcf		blinking_better_gas				; NO - clear blinking flag
+	bcf		better_gas_blinking				; NO - clear blinking flag
 	return
 check_gas_best_common:						; with gas to be checked in check_gas_num (1-5)
 ;											; and  current gas       in lo            (1-5)
 	;
 	; opt_gas_change		res 5	; has offset of 10 bytes from opt_gas_type
 	; opt_dil_change		res 5	; has offset of 10 bytes from opt_dil_type
 	; get gas data
 	decf	check_gas_num,W					; (1-5) -> (0-4) into WREG to be used as index
-	movff	PLUSW1,check_gas_O2_ratio		; load O2 ratio (%) of current gas/dil into check_gas_O2_ratio
+	movff	PLUSW1,check_gas_O2_ratio		; copy O2 ratio (%) of current gas/dil to check_gas_O2_ratio
 	addlw	.20								; add offset of 20 bytes to index type in opt_gas_type/opt_dil_type
-	movff	PLUSW1,check_gas_type			; load type of current gas/dil into check_gas_type (0=disabled, 1=first, 2=travel/normal, 3=deco/-)
+	movff	PLUSW1,check_gas_type			; copy type of current gas/dil to check_gas_type (0=disabled, 1=first, 2=travel/normal, 3=deco/-)
 	addlw	.10								; add offset of 10 bytes to index change depth in opt_gas_change/opt_dil_change
-	movff	PLUSW1,check_gas_depth			; load change depth of current gas/dil into check_gas_depth
+	movff	PLUSW1,check_gas_depth			; copy change depth of current gas/dil to check_gas_depth
-	; check if gas is usable (i.e. not disabled)
+	MOVII	ppO2_max_default,sub_b			; select default ppO2 max for first / travel / normal gas
-	tstfsz	check_gas_type					; type = disabled (0)?
+	; check if gas is available (i.e. not disabled)
-	bra		check_gas_best_common0			; NO  - continue checks
+	tstfsz	check_gas_type					; type = disabled (0) ?
+	bra		check_gas_best_common1			; NO  - continue checks
 	movf	check_gas_num,W					; YES - get the number of the gas to be checked (1-5)
 	cpfseq	lo								;     - is this the currently used gas?
 	return									;       NO  - skip disabled gases which are not the current gas
-	bra		check_gas_best_common1			;       YES - a gas in use overrides it's disabled status, therefore treat it as available
+	bra		check_gas_best_common3			;       YES - a gas in use overrides it's disabled status, therefore treat it as available
-check_gas_best_common0:
+check_gas_best_common1:
-	; skip deco gases (type=3) if not in deco mode, but search among all enabled gases when in loop or bailout mode
+	; skip deco gases (type=3) if there are no stops, but include them when in bailout mode
-	movlw	.3
+	movlw	.3								; coding for deco gas
-	cpfseq	check_gas_type					; type = deco (3)?
+	cpfseq	check_gas_type					; type = deco (3) ?
-	bra		check_gas_best_common1			; NO  - proceed
+	bra		check_gas_best_common3			; NO  - first or travel/normal then, ok to use
-	btfsc	FLAG_bailout_mode				; YES - in bailout?
+	btfsc	bailout_mode					; YES - in bailout?
-	bra		check_gas_best_common1			;       YES - proceed, include deco gases
+	bra		check_gas_best_common2			;       YES - ok to use (using deco gases is always allowed when in bailout)
-	movff	char_O_main_status,WREG			;       NO  - get main deco mode
-	btfsc	WREG,DECO_MODE_LOOP_FLAG		;           - in loop mode?
+	TSTOSC	opt_extended_stops				;       NO  - extended stops activated?
-	bra		check_gas_best_common1			;             YES - proceed, include deco gases
+	bra		check_gas_best_common1a			;             YES - (1)
-	movff	char_O_deco_info,WREG			;             NO  - get deco info vector
+	movff	char_O_deco_info,WREG			;  	          NO  - get deco info vector
 	btfss	WREG,deco_flag					;                 - in deco mode (deco_flag set), i.e. use of deco gases allowed?
 	return									;                   NO  - skip deco gas while not in deco mode
-check_gas_best_common1:						;                   YES - proceed
+	bra		check_gas_best_common2			;                   YES - ok to use
-;	; check if gas change depth is below minimum change depth
+check_gas_best_common1a:
-;	movlw	minimum_change_depth			; for value see definition in hwos.inc
+	movff	char_O_deco_depth+0,WREG		;             (1) - get depth of the first stop
-;	cpfsgt	check_gas_depth					; change depth of checked gas > minimum_change_depth?
+	tstfsz	WREG							;                 - is there any stop?
-;	return									; NO - change depth not deep enough, skip and check next gas
+	bra		check_gas_best_common2			;                   YES - ok to use a deco gas
+	movf	check_gas_num,W					;                   NO  - get the number of the gas to be checked (1-5)
+	cpfseq	lo								;                       - is this the currently used gas?
+	return									;                         NO  - skip this deco gas
+	;bra	check_gas_best_common2			;                         YES - keep this deco gas as continued allowed
+check_gas_best_common2:
+	MOVII	ppO2_max_deco,sub_b				; replace by ppO2 max for a deco gas
+check_gas_best_common3:
 	; check if gas is usable, i.e. its change depth is below or equal to the current depth
-	movf	curr_depth,W					; load current depth (in m) into WREG
+	movf	depth_meter,W					; load current depth (in m) into WREG
 	cpfslt	check_gas_depth					; change depth of checked gas < (shallower than) current depth?
-	bra		check_gas_best_common2			; NO  - gas is usable
+	bra		check_gas_best_common4			; NO  - gas is usable
 	return									; YES - gas is not usable
-check_gas_best_common2:
+check_gas_best_common4:
 	; check if this gas is the first best gas candidate
 	movf	best_gas_num,W					; get best gas found so far (1-5) or 0 if none found yet
 	tstfsz	WREG							; has a best gas candidate been found yet?
-	bra		check_gas_best_common3			; YES - check if the new one is better than the one we have so far
+	bra		check_gas_best_common5			; YES - check if the new one is better than the one we have so far
-	bra		check_gas_best_common4			; NO  - no need to do the above mentioned check
+	bra		check_gas_best_common6			; NO  - no need to do the above mentioned check
-check_gas_best_common3:
+check_gas_best_common5:
 	; check if the change depth of the checked gas is < (shallower) than the change depth of the best gas found so far
 	movf	best_gas_depth,W				; load change depth of best gas so far into WREG
 	cpfslt	check_gas_depth					; change depth of checked gas < (shallower than) change depth of best gas so far?
 	return									; NO - this gas is not better than the best already found
-check_gas_best_common4:
+check_gas_best_common6:
 	; check if the gas fits into the ppO2 limits
-	movff	check_gas_O2_ratio,xB+0			; xB = O2 ratio, xA is still loaded with (p_amb / 10)
+	movff	check_gas_O2_ratio,xB+0			; xB = O2 ratio, xA is still loaded with (absolute pressure / 10)
 	clrf	xB+1
-	call	mult16x16						; xC = O2 ratio * (p_amb / 10)
+	call	mult16x16						; xC = O2 ratio * (absolute pressure / 10), result in 0.1 mbar
 	; check for very high ppO2
-	tstfsz	xC+2							; O2_ratio * p_amb / 10 > 65536, i.e. ppO2 > 6.55 bar ?
+	tstfsz	xC+2							; O2_ratio * absolute pressure / 10 > 65536, i.e. ppO2 > 6.55 bar ?
 	return									; YES - gas is not usable
-	btfsc	xC+1,7							; check if ppO2 > 3.30 bar
+	btfsc	xC+1,7							; ppO2 > 3.30 bar ?
 	return									; YES - gas is not usable
+	MOVII	xC,sub_a						; NO  - gas may be usable
+	; check for high ppO2
+	call	cmpU16							; sub_a - sub_b
+	btfss	neg_flag						; within limit?
+	return									; NO - too high, gas is not usable
 	; check for low ppO2
-	movff	xC+0,sub_a+0
+	MOVII	ppO2_min,sub_b					; copy minimum ppO2 to sub_b
-	movff	xC+1,sub_a+1
+	call	cmpU16							; sub_a - sub_b
-	movf	ppO2_min,W
-	mullw	.100							; char_I_ppO2_min * 100
-	movff	PRODL,sub_b+0
-	movff	PRODH,sub_b+1
-	call	subU16							; sub_c = sub_a - sub_b
 	btfsc	neg_flag						; within limit?
 	return									; NO - too low, gas is not usable
-	; check for high ppO2
-	movf	ppO2_max,W
-	mullw	.100							; ppO2_max * 100
-	movff	PRODL,sub_b+0
-	movff	PRODH,sub_b+1
-	infsnz	sub_b+0,F						; add 1 mbar to allowance to avoid exclusion on equal
-	incf	sub_b+1,F
-	call	subU16							; sub_c = sub_a - sub_b
-	btfss	neg_flag						; within limit?
-	return									; NO - too high, gas is not usable
 	; we have a (new) best gas
 	movff	check_gas_num,  best_gas_num	; set checked gas (1-5) as best gas
 	movff	check_gas_depth,best_gas_depth	; memorize its change depth
 	return
 ;=============================================================================
 ; Check for Auto-SP
 ;
+IFDEF _ccr_pscr
 check_dive_autosp:						; check for Auto-SP
 	movff	opt_ccr_mode,WREG			; =0: Fixed SP, =1: Sensor, =2: Auto SP
 	sublw	.2							; opt_ccr_mode = 2 (Auto SP)?
 	bz		check_dive_autosp2			; YES - check
 	return								; NO  - return for sensor or fixed mode
 check_dive_autosp2:
 	; Check SP2
-	btfsc	sp2_switched				; SP 2 used so far?
+	btfsc	FLAG_SP2_used				; SP 2 used so far?
 	bra		check_dive_autosp3			; YES - continue with SP 3
-	movff	char_I_setpoint_change+1,lo	; NO  - get depth in m
+	movff	opt_setpoint_change+1,lo	; NO  - get depth in m
 	tstfsz	lo							;     - SP change depth = 0 ?
 	bra		check_dive_autosp2a			;       NO  - continue
 	bra		check_dive_autosp3			;       YES - continue with SP 3
 check_dive_autosp2a:
 	decf	lo,W						; SP change depth -1 -> WREG
-	cpfsgt	curr_depth					; current depth > change depth - 1 ?
+	cpfsgt	depth_meter					; current depth > change depth - 1 ?
 	bra		check_dive_autosp3			; NO  - continue with SP 3
 	; auto switch to SP2
-	movff	char_I_setpoint_cbar+1,char_I_const_ppO2 ; YES - use SP
+	movff	opt_setpoint_cbar+1,char_I_const_ppO2 ; YES - use SP
 	rcall	xmit_sp_set_flag			;     - send SP to external devices
-	bsf		sp2_switched				;     - set SP 2 used flag
+	bsf		FLAG_SP2_used				;     - set SP 2 used flag
 check_dive_autosp3:
 	; Check SP3
-	btfsc	sp3_switched				; SP 3 used so far?
+	btfsc	FLAG_SP3_used				; SP 3 used so far?
 	bra		check_dive_autosp4			; YES - continue with SP 4
-	movff	char_I_setpoint_change+2,lo	; NO  - get depth in m
+	movff	opt_setpoint_change+2,lo	; NO  - get depth in m
 	tstfsz	lo							;     - SP change depth = 0 ?
 	bra		check_dive_autosp3a			;       NO  - continue
 	bra		check_dive_autosp4			;       YES - continue with SP 4
 check_dive_autosp3a:
 	decf	lo,W						; SP change depth -1 -> WREG
-	cpfsgt	curr_depth					; current depth > change depth - 1 ?
+	cpfsgt	depth_meter					; current depth > change depth - 1 ?
 	bra		check_dive_autosp4			; NO  - continue with SP 4
 	; auto switch to SP3
-	movff	char_I_setpoint_cbar+2,char_I_const_ppO2 ; YES - use SP
+	movff	opt_setpoint_cbar+2,char_I_const_ppO2 ; YES - use SP
 	rcall	xmit_sp_set_flag			;     - send SP to external devices
-	bsf		sp3_switched				;     - set SP 3 used flag
+	bsf		FLAG_SP3_used				;     - set SP 3 used flag
 check_dive_autosp4:
 	; Check SP4
-	btfsc	sp4_switched				; SP 4 used so far?
+	btfsc	FLAG_SP4_used				; SP 4 used so far?
 	bra		check_dive_autosp5			; YES - continue with SP 5
-	movff	char_I_setpoint_change+3,lo ; NO  - get depth in m
+	movff	opt_setpoint_change+3,lo	; NO  - get depth in m
 	tstfsz	lo							;     - SP change depth = 0 ?
 	bra		check_dive_autosp4a			;       NO  - continue
-	bra		check_dive_autosp5			;        YES - continue with SP 5
+	bra		check_dive_autosp5			;       YES - continue with SP 5
 check_dive_autosp4a:
 	decf	lo,W						; SP change depth -1 -> WREG
-	cpfsgt	curr_depth					; current depth > change depth - 1 ?
+	cpfsgt	depth_meter					; current depth > change depth - 1 ?
 	bra		check_dive_autosp5			; NO  - continue with SP 5
 	; auto switch to SP4
-	movff	char_I_setpoint_cbar+3,char_I_const_ppO2 ; YES - use SP
+	movff	opt_setpoint_cbar+3,char_I_const_ppO2 ; YES - use SP
 	rcall	xmit_sp_set_flag			;     - send SP to external devices
-	bsf		sp4_switched				;     - set SP 4 used flag
+	bsf		FLAG_SP4_used				;     - set SP 4 used flag
 check_dive_autosp5:
 	; Check SP5
-	btfsc	sp5_switched				; SP 5 used so far?
+	btfsc	FLAG_SP5_used				; SP 5 used so far?
 	bra		check_dive_autosp6			; YES - done
-	movff	char_I_setpoint_change+4,lo	; NO  - get depth in m
+	movff	opt_setpoint_change+4,lo	; NO  - get depth in m
 	tstfsz	lo							;     - SP change depth = 0 ?
 	bra		check_dive_autosp5a			;       NO  - continue
 	bra		check_dive_autosp6			;       YES - done
 check_dive_autosp5a:
 	decf	lo,W						; SP change depth -1 -> WREG
-	cpfsgt	curr_depth					; current depth > change depth - 1 ?
+	cpfsgt	depth_meter					; current depth > change depth - 1 ?
 	bra		check_dive_autosp6			; NO  - done
 	; auto switch to SP5
-	movff	char_I_setpoint_cbar+4,char_I_const_ppO2 ; YES - use SP
+	movff	opt_setpoint_cbar+4,char_I_const_ppO2 ; YES - use SP
 	rcall	xmit_sp_set_flag			;     - send SP to external devices
-	bsf		sp5_switched				;     - set SP 5 used flag
+	bsf		FLAG_SP5_used				;     - set SP 5 used flag
 check_dive_autosp6:
 	return
 xmit_sp_set_flag:
-	movff	char_I_const_ppO2,WREG
+IFDEF _external_sensor
 	call	transmit_setpoint			; transmit current setpoint from WREG (in cbar) to external electronics
-	bsf		setpoint_changed			; set flag (for profile)
+ENDIF
-	bsf		event_occured				; set event flag
+	bsf		event_occured				; set global   event flag
+	bsf		event_SP_change				; set setpoint event flag
 	return
+ENDIF	; _ccr_pscr
+;=============================================================================
 set_logbook_marker:
-	bcf		FLAG_set_marker				; clear flag
+	bcf		request_set_marker			; clear request flag
-	movlw	d'6'						; set type of alarm (manual marker)
+	movlw	d'6'						; set type of alarm: manual marker
-	movwf	AlarmType					; copy to alarm register
+	movwf	alarm_type					; copy to alarm register
 	bsf		event_occured				; set event flag
 	return
 ;=============================================================================
 ; Setup everything to enter dive mode
 ;
 	global	dive_boot_oc_bail
 dive_boot_oc_bail:
 	; copy opt_gas_types into backup (for "lost gas" feature)
-	movff	opt_gas_type+0,opt_gas_type_backup+0		; 0=Disabled, 1=First, 2=Travel, 3=Deco
+	movff	opt_gas_type+0,opt_gas_type_backup+0	; 0=Disabled, 1=First, 2=Travel, 3=Deco
-	movff	opt_gas_type+1,opt_gas_type_backup+1		; 0=Disabled, 1=First, 2=Travel, 3=Deco
+	movff	opt_gas_type+1,opt_gas_type_backup+1	; 0=Disabled, 1=First, 2=Travel, 3=Deco
-	movff	opt_gas_type+2,opt_gas_type_backup+2		; 0=Disabled, 1=First, 2=Travel, 3=Deco
+	movff	opt_gas_type+2,opt_gas_type_backup+2	; 0=Disabled, 1=First, 2=Travel, 3=Deco
-	movff	opt_gas_type+3,opt_gas_type_backup+3		; 0=Disabled, 1=First, 2=Travel, 3=Deco
+	movff	opt_gas_type+3,opt_gas_type_backup+3	; 0=Disabled, 1=First, 2=Travel, 3=Deco
-	movff	opt_gas_type+4,opt_gas_type_backup+4		; 0=Disabled, 1=First, 2=Travel, 3=Deco
+	movff	opt_gas_type+4,opt_gas_type_backup+4	; 0=Disabled, 1=First, 2=Travel, 3=Deco
-	; done
 	return
 	global	dive_boot_oc
 dive_boot_oc:
 	; set-up registers
-	rcall	get_first_gas_to_WREG		; get first gas (1-5) into WREG
+	rcall	get_first_gas_to_WREG					; get first gas (1-5) into WREG
-	rcall	setup_gas_registers			; set-up of gas parameters of currently breathed gas (with WREG = gas 1-5)
+	rcall	setup_gas_registers						; set-up of gas parameters of currently breathed gas (with WREG = gas 1-5)
-	rcall	deco_setup_oc_gases			; set-up of gas list for deco calculations (with WREG = gas 1-5)
+	rcall	deco_setup_oc_gases						; set-up of gas list for deco calculations (with WREG = gas 1-5)
 	return
+;=============================================================================
+IFDEF _ccr_pscr
 	global	dive_boot_cc
 dive_boot_cc:
 	; copy opt_dil_types into backup (for "lost diluent" feature)
-	movff	opt_dil_type+0,opt_dil_type_backup+0		; 0=Disabled, 1=First, 2=Normal
+	movff	opt_dil_type+0,opt_dil_type_backup+0	; 0=Disabled, 1=First, 2=Normal
-	movff	opt_dil_type+1,opt_dil_type_backup+1		; 0=Disabled, 1=First, 2=Normal
+	movff	opt_dil_type+1,opt_dil_type_backup+1	; 0=Disabled, 1=First, 2=Normal
-	movff	opt_dil_type+2,opt_dil_type_backup+2		; 0=Disabled, 1=First, 2=Normal
+	movff	opt_dil_type+2,opt_dil_type_backup+2	; 0=Disabled, 1=First, 2=Normal
-	movff	opt_dil_type+3,opt_dil_type_backup+3		; 0=Disabled, 1=First, 2=Normal
+	movff	opt_dil_type+3,opt_dil_type_backup+3	; 0=Disabled, 1=First, 2=Normal
-	movff	opt_dil_type+4,opt_dil_type_backup+4		; 0=Disabled, 1=First, 2=Normal
+	movff	opt_dil_type+4,opt_dil_type_backup+4	; 0=Disabled, 1=First, 2=Normal
-	; clear flags
-	bcf		FLAG_bailout_mode			; =1: bailout
-	bcf		setpoint_fallback			; =1: fallback to SP1 due to external O2 sensor failure
 	; set-up registers
-	rcall	get_first_dil_to_WREG		; get first diluent (1-5) into WREG
+	rcall	get_first_dil_to_WREG					; get first diluent (1-5) into WREG
-	rcall	setup_dil_registers			; set-up of diluent parameters for currently breathed diluent (with WREG = current diluent 1-5)
+	rcall	setup_dil_registers						; set-up of diluent parameters for currently breathed diluent (with WREG = current diluent 1-5)
-	rcall	deco_setup_cc_diluents		; set-up of diluent list for deco calculations (with WREG = current diluent 1-5)
+	rcall	deco_setup_cc_diluents					; set-up of diluent list for deco calculations (with WREG = current diluent 1-5)
 	; done
 	return
 dive_boot_cc_part2:
 	; revoke sensors from usage if they do not have a valid calibration
 	bsf		use_O2_sensor1
 	bsf		use_O2_sensor2
 	bcf		use_O2_sensor1
 	btfss	sensor2_calibrated_ok
 	bcf		use_O2_sensor2
 	btfss	sensor3_calibrated_ok
 	bcf		use_O2_sensor3
+IFDEF _external_sensor
 	; check for external HUD/ppO2 Monitor
 	btfss	optical_input				; do we have an optical input?
 	bra		dive_boot_cc_part2_1		; NO
-	; copy (initial) valid flags from HUD/ppO2 Monitor
+	btfsc	sensor1_active				; YES - copy valid flags from HUD/ppO2 Monitor
-	btfsc	sensor1_active
+	bsf		use_O2_sensor1				;     - ...
-	bsf		use_O2_sensor1
+	btfsc	sensor2_active				;     - ...
-	btfsc	sensor2_active
+	bsf		use_O2_sensor2				;     - ...
-	bsf		use_O2_sensor2
+	btfsc	sensor3_active				;     - ...
-	btfsc	sensor3_active
+	bsf		use_O2_sensor3				;     - ...
-	bsf		use_O2_sensor3
+ENDIF
 dive_boot_cc_part2_1:
 	; In pSCR mode, only settings 0 (calculated ppO2) and 1 (ppO2 from sensors) are defined.
 	; In case we still have 3 (auto SP) selected out of previous CCR mode, we reset to 0.
 	btfss	FLAG_pscr_mode
 	bra		dive_boot_cc_part2_2
 	sublw	.2							; opt_ccr_mode = 1 (Auto SP)?
 	bnz		dive_boot_cc_part2_2
 	movlw	.0
 	movff	WREG,opt_ccr_mode
 dive_boot_cc_part2_2:
-	bsf		setpoint_changed			; set flag (for profile)
+	bsf		event_SP_change				; set setpoint event flag
-	bcf		sp2_switched				; =1: this setpoint has been auto-selected already
-	bcf		sp3_switched				; =1: this setpoint has been auto-selected already
-	bcf		sp4_switched				; =1: this setpoint has been auto-selected already
-	bcf		sp5_switched				; =1: this setpoint has been auto-selected already
 	; Start with SP1 (CCR) or 0 (pSCR) as default.
 	; If in sensor mode, this value will be overwritten by calc_deko_divemode_sensor
-	clrf	WREG						; preload WREG with setpoint value 0 for pSCR calculated
+	clrf	WREG						; pre-load WREG with setpoint value 0 for pSCR calculated
-	btfsc	FLAG_ccr_mode				; are we in CCR mode?
+	btfsc	FLAG_ccr_mode				; in CCR mode?
-	movff	char_I_setpoint_cbar+0,WREG	; YES - get value of setpoint 1
+	movff	opt_setpoint_cbar+0,WREG	; YES - get value of setpoint 1 into WREG
 	movff	WREG,char_I_const_ppO2		; write setpoint to deco engine
+IFDEF _external_sensor
 	call	transmit_setpoint			; transmit current setpoint from WREG (in cbar) to external electronics
 	goto	calc_deko_divemode_sensor	; read & process sensor data (and return)
+ELSE
+	return								; done
+ENDIF
+ENDIF	; _ccr_pscr
+;=============================================================================
 diveloop_boot:
 	; do the basic initialization
 	call	restart_set_modes_and_flags
 	; stop accelerometer and compass
 	call	I2C_sleep_accelerometer
 	call	I2C_sleep_compass
-	; reset max pressure aka max depth
+	; do an early initialization of all deco engine output variables to
-	clrf	WREG
+	; avoid glitches in the display outputs during deco engine start-up
-	movff	WREG,max_pressure+0
+	call	deco_init_output_vars;		; (C-code)
-	movff	WREG,max_pressure+1
+	banksel	common						; back to bank common
-	; initialize press needs to zero and invalid (not yet computed) state
+	; reset max relative pressure (max depth)
-	clrf	WREG						; set WREG to 0
+	bsf		reset_max_pressure			; request ISR to reset the max pressure
+IFDEF _min_depth_option
+	; reset the resettable min/max relative pressure (trip-wise min/max depth)
+	bsf		reset_trip_pressure			; request ISR to reset the resettable min/max pressure
+ENDIF
 IFDEF _cave_mode
-	movff	WREG,char_I_backtrack_time	; clear backtracking time (index to char_I_backtrack_depth)
+	; initialize the cave mode
-	movff	WREG,char_I_backtrack_depth	; prime first entry with depth 0
+	bsf		cave_mode					; enable cave mode by default
-ENDIF
+	movff	opt_calc_asc_gasvolume,WREG	; get gas needs calculation mode (0= off, 1= on, 2= cave mode)
-	bsf		WREG,int_is_zero			; set zero flag
+	xorlw	.2							; coding for cave mode
-	bsf		WREG,int_invalid_flag		; set invalid flag (additionally)
+	tstfsz	WREG						; cave mode enabled?
-	banksel	int_O_ascent_pres_need		; select bank with shared output vars
+	bcf		cave_mode					; NO - disable cave mode again
-	movwf	int_O_ascent_pres_need+1	; Set flags for tank pressure needs = 0 before p2_deco.c
+ENDIF
-	movwf	int_O_ascent_pres_need+3	; can do it. If this is not done here and the gas needs
-	movwf	int_O_ascent_pres_need+5	; custom view is shown before p2_deco.c completes the first
-	movwf	int_O_ascent_pres_need+7	; deco calculation, some rubbish numbers from last dive or
-	movwf	int_O_ascent_pres_need+9	; simulation may be shown
-	banksel	common						; back to bank common
 	; configure the deco engine
-	clrf	hi
+	clrf	hi							; start with everything disabled
-	bsf		hi,DECO_Z_FACTOR_FLAG		; enable Z factor mode by default
-	TSTOSS	opt_ZfactorUse				; shall use Z factor mode?
+	TSTOSC	opt_ZfactorUse				; shall use Z factors?
-	bcf		hi,DECO_Z_FACTOR_FLAG		; NO - disable again
+	bsf		hi,DECO_Z_FACTOR_FLAG		; YES - enable Z factors
+	TSTOSC	opt_extended_stops			; shall make extended stops?
+	bsf		hi,DECO_EXTENDED_STOPS		; YES - enable extended stops
 IFDEF _rx_functions
-	bsf		hi,DECO_TR_FUNCTIONS		; enable TR mode by default
+	btfsc	tr_functions_activated		; TR functions activated?
-	btfss	FLAG_tr_enabled				; shall use TR mode?
+	bsf		hi,DECO_TR_FUNCTIONS		; YES - enable TR functions
-	bcf		hi,DECO_TR_FUNCTIONS		; NO - disable again
+ENDIF
-ENDIF
 	movff	hi,char_O_main_status		; bank-safe copy to deco engine
 	movff	char_O_deco_status,lo		; bank-safe read
-	bsf		lo,DECO_STATUS_0_FLAG		; set init-  | ATTENTION: The deco engine must be started in init state! If omitted, it may
+	bsf		lo,DECO_START_NORM			; set   flag for doing a  normal      plan,
-	bsf		lo,DECO_STATUS_1_FLAG		;     state, |            enter an infinite loop at some point in time and brick the OSTC!
+	bcf		lo,DECO_START_ALT			; clear flag for doing an alternative plan,
-	bcf		lo,DECO_PLAN_FLAG			; normal plan mode,
+	bsf		lo,DECO_INITIALIZE			; set   flag for initializing the deco engine
-	bcf		lo,DECO_VOLUME_FLAG			; disable gas volume calculation, and
 	bcf		lo,DECO_ASCENT_FLAG			; disable delayed ascent calculation
 	movff	lo,char_O_deco_status		; bank-safe copy back to deco engine
-	clrf	WREG
+	; configure distance between actual depth and depth used for deco calculation
-	movff	WREG,char_O_deco_warnings	; clear any deco warnings remaining from last dive
+	movlw	deco_distance
-	movff	WREG,char_O_deco_info		; clear any deco infos    remaining from last dive
+	movff	WREG,char_I_deco_distance
-	movlw	deco_distance				; load distance between actual depth and depth used for deco calculation
+	; disable "fast forward" function
-	movff	WREG,char_I_deco_distance	; write distance to the deco engine
+	movlw	.0
+	movff	WREG,char_I_sim_advance_time
-	movff	opt_last_stop,char_I_depth_last_deco	; write last stop depth to deco engine
-	movff	opt_GF_low,char_I_GF_Low_percentage		; write GF low  to deco engine
+	; write last stop depth to deco engine
-	movff	opt_GF_high,char_I_GF_High_percentage	; write GF high to deco engine
+	movff	opt_last_stop,char_I_depth_last_deco
-	bcf		onesectoggle				; clear toggle bit for calculation phasing
+	; initialize max depth for apnoe mode
-	bcf		use_agf						; start with normal GF set
+	CLRI	apnoe_max_pressure
-	bcf		divemode_menu				; clear dive mode menu flag
-	bcf		alternative_divelayout		; start with default layout
+	; reset minimum temperature, ISR-safe 2 byte copy
-	bcf		blinking_depth_prev			; clear flag for blinking depth
+	SMOVII	temperature_cur,temperature_min
-	bcf		blinking_depth_toggle		; clear flag for blinking depth
-	bcf		blinking_depth_warning		; clear flag for blinking depth as warning
+	; ISR-safe copy of start-of-dive date and time for logbook (6 bytes in total)
-	bcf		blinking_depth_attention	; clear flag for blinking depth as attention
+	SMOVSS	rtc_year,start_year
-	bcf		max_depth_greater_100m		; clear flag for last max/avg depth was > 100 m
+	MOVII	int_O_CNS_current,CNS_start		; save current CNS at beginning of dive, but
-	movlw	d'1'
+	bcf		CNS_start+1,int_warning_flag	; without warning   flag
-	movwf	apnoe_max_pressure+0
+	bcf		CNS_start+1,int_attention_flag	; without attention flag
-	clrf	apnoe_max_pressure+1
-;	clrf	apnoe_surface_mins
+	; save supersaturation at beginning of dive (only lower byte is used for value)
-;	clrf	apnoe_surface_secs
+	movff	int_O_lead_supersat+0,supersat_start
-	; copy date and time for logbook
+	clrf	menu_pos_cur
-	movff	year,start_year
+	clrf	active_premenu				; reset to zero (0= no pre-menu task)
-	movff	month,start_month
+	bsf		o2_sensors_agree			; initialize sensors disagree warning system
-	movff	day,start_day
-	movff	hours,start_hours
+	clrf	safety_stop_countdown		; clear safety stop count-down
-	movff	mins,start_mins
+	CLRI	last_pressure_velocity		; initialize last pressure for velocity calculation
-	movff	int_O_CNS_fraction+0,CNS_start+0 ; save CNS value at beginning of dive
+	CLRI	dive_timeout_timer			; initialize timeout counter
-	movff	int_O_CNS_fraction+1,WREG		 ; get high byte to WREG
-	bcf		WREG,int_warning_flag			 ; clear warning   flag
+	movlw	.1							; initialize the sampling timer such that the 1st sampling ...
-	bcf		WREG,int_attention_flag			 ; clear attention flag
+	movwf	sampling_timer				; ... trigger will be given as soon as possible
-	movff	WREG,CNS_start+1				 ; move high byte on
-	movff	int_O_gradient_factor+0,GF_start ; save GF value at beginning of dive (only lower byte used for value)
+	clrf	message_page				; initialize message page counter
+	clrf	alarm_type					; clear all alarms
-	bcf		no_more_divesecs			 ; =1: do no longer show seconds in dive mode
-	bcf		divemode_menu_active
+	; clear the total dive average depth
-	clrf	menupos1
+	CLRI	pressure_rel_avg_total		; average depth
-	clrf	menupos2					 ; reset to zero (Zero=no pre-menu or simulator task)
+	CLRI	divesecs_avg_total			; time  accumulator
-	bsf		sensors_agree				 ; init of sensors disagree warning system
+	clrf	pressure_rel_accu_total+0	; depth accumulator
+	clrf	pressure_rel_accu_total+1
-	bcf		show_safety_stop			; =1: show the safety stop
+	clrf	pressure_rel_accu_total+2
-	clrf	safety_stop_countdown		; clear count-down
+	clrf	pressure_rel_accu_total+3
-	clrf	samplesecs					; timer for data logging
-	clrf	apnoe_timeout_counter		; timeout in minutes
-	clrf	timeout_counter1+0			; takes care of the timeout (low  byte)
-	clrf	timeout_counter1+1			; takes care of the timeout (high byte)
-	clrf	AlarmType					; Clear all alarms
-	bcf		event_occured				; clear flag
-	clrf	average_divesecs_total+0	; clear non-resettable time accumulator
-	clrf	average_divesecs_total+1
-	clrf	average_depth_hold_total+0	; clear non-resettable average depth
-	clrf	average_depth_hold_total+1
-	clrf	average_depth_hold_total+2
-	clrf	average_depth_hold_total+3
-	call	reset_average				; reset the resettable average depth
 IFDEF _rx_functions
-	btfss	FLAG_tr_enabled				; TR functions enabled?
+	btfss	tr_functions_activated		; TR functions activated?
 	bra		diveloop_boot_0				; NO  - skip TR function initialization
 										; YES - initialize TR function variables
-	banksel	int_O_sac_rate
-	clrf	int_O_sac_rate+0			; clear low byte      of SAC rate
-	clrf	int_O_pressure_need+0		; clear low byte      of 1st pressure need    value
-	clrf	int_O_pressure_need+2		; clear low byte      of 2nd pressure need    value
 	banksel	int_IO_pressure_value
-	clrf	int_IO_pressure_value+0		; clear low byte      of 1st pressure reading value
+	clrf	WREG						; clear WREG
-	clrf	int_IO_pressure_value+2		; clear low byte      of 2nd pressure reading value
+	bsf		WREG,int_not_avail_flag		; set   WREG to coding for integer numbers -> data not available
-	clrf	int_I_pressure_drop+0		; clear low byte      of 1st pressure drop    value
+	clrf	int_IO_pressure_value+0		; clear   low  byte   of 1st pressure reading value
-	clrf	int_I_pressure_drop+2		; clear low byte      of 2nd pressure drop    value
+	movwf	int_IO_pressure_value+1		; copy to high byte   of 1st pressure reading value
+	clrf	int_IO_pressure_value+2		; clear   low  byte   of 2nd pressure reading value
+	movwf	int_IO_pressure_value+3		; copy to high byte   of 2nd pressure reading value
+	clrf	int_I_pressure_drop+0		; clear   low  byte   of 1st pressure drop    value
+	movwf	int_I_pressure_drop+1		; copy to high byte   of 1st pressure drop    value
+	clrf	int_I_pressure_drop+2		; clear   low  byte   of 2nd pressure drop    value
+	movwf	int_I_pressure_drop+3		; copy to high byte   of 1st pressure drop    value
 	clrf	char_I_pressure_gas+0		; clear gas selection of 1st pressure reading
 	clrf	char_I_pressure_gas+1		; clear gas selection of 2nd pressure reading
 	clrf	char_I_pressure_age+0		; clear age           of 1st pressure reading
 	clrf	char_I_pressure_age+1		; clear age           of 2nd pressure reading
 	clrf	char_I_pressure_stat+0		; clear status        of 1st pressure reading
 	clrf	char_I_pressure_stat+1		; clear status        of 2nd pressure reading
-	clrf	WREG						; clear WREG
-	bsf		WREG,int_not_avail_flag		; set   WREG to coding for integer numbers -> data not available
-	banksel	int_O_sac_rate
-	movwf	int_O_sac_rate+1			; copy to high byte     of SAC rate
-	movwf	int_O_pressure_need+1		; copy to high byte     of 1st pressure need    value
-	movwf	int_O_pressure_need+3		; copy to high byte     of 1st pressure need    value
-	banksel	int_IO_pressure_value
-	movwf	int_IO_pressure_value+1		; copy to high byte     of 1st pressure reading value
-	movwf	int_IO_pressure_value+3		; copy to high byte     of 2nd pressure reading value
-	movwf	int_I_pressure_drop+1		; copy to high byte     of 1st pressure drop    value
-	movwf	int_I_pressure_drop+3		; copy to high byte     of 1st pressure drop    value
 	banksel	gas__last_1st				; select bank with vars for pressure drop calculation
 	setf	gas__last_1st				; invalidate last gas of 1st reading
-	setf	gas__last_2nd				; invalidate last gas of  2nd reading
+	setf	gas__last_2nd				; invalidate last gas of 2nd reading
 	banksel	common						; back to bank common
-ENDIF
+ENDIF	; _rx_functions
 diveloop_boot_0:
-	bcf		decostop_active				; clear flag for being in deco
 	setf	best_gas_number				; initialize best gas     as not computed yet (255)
+IFDEF _ccr_pscr
 	setf	best_dil_number				; initialize best diluent as not computed yet (255)
-	bcf		better_gas_available		; =1: a better gas     is available and a gas change is advised
+ENDIF
-	bcf		better_dil_available		; =1: a better diluent is available and a gas change is advised
 	rcall	dive_boot_oc_bail			; basic settings required for all modes
 	btfsc	FLAG_oc_mode				; in OC mode?
 	rcall	dive_boot_oc				; YES - add OC mode settings
+IFDEF _ccr_pscr
 	btfsc	FLAG_ccr_mode				; in CCR mode?
 	rcall	dive_boot_cc				; YES - add CC mode settings
 	btfsc	FLAG_ccr_mode				; in CCR mode?
 	rcall	dive_boot_cc_part2			; YES - add CC sensor and SP settings
 	btfsc	FLAG_pscr_mode				; in pSCR mode?
 	rcall	dive_boot_cc				; YES - add CC mode settings
 	btfsc	FLAG_pscr_mode				; in pSCR mode?
 	rcall	dive_boot_cc_part2			; YES - add CC sensor and SP settings
+ENDIF
 	call	ghostwriter_short_header	; write short header with dive number into profile memory
+	call	init_recording_params		; set up all the divisors for dive data recording
-	btfsc	simulatormode_active
-	bra		diveloop_boot_1
+	; setup gas selector flag (required to have better gas working)
+	bsf		is_diluent_menu				; default to using diluents
-	; normal mode = surface pressure is the pressure 30 minutes before dive
+	btfsc	FLAG_ccr_mode				; in CCR mode?
-	SAFE_2BYTE_COPY last_surfpressure_30min, int_I_pres_surface	;copy surface pressure to deco routine
+	bra		diveloop_boot_3				; YES - default was right
-	SAFE_2BYTE_COPY last_surfpressure_30min, last_surfpressure	;copy surface pressure to last_surfpressure for correct depth
+	btfsc	FLAG_pscr_mode				; in pSCR mode?
-	bra		diveloop_boot_2
+	bra		diveloop_boot_3				; YES - default was right
+	bcf		is_diluent_menu				; NO to both - revert to using OC gases
-diveloop_boot_1:
-	; simulator mode: set surface pressure to 1 bar because simulated depths are also based on 1 bar surface pressure
-	movlw	LOW  .1000
-	movff	WREG,int_I_pres_surface+0	; LOW  copy surface pressure to deco routine
-	movlw	HIGH .1000
-	movff	WREG,int_I_pres_surface+1	; HIGH copy surface pressure to deco routine
-diveloop_boot_2:
-	SAFE_2BYTE_COPY temperature,minimum_temperature ; reset minimum temperature registers
-	call	init_recording_params		; set up all the divisors
-	bsf		FLAG_diluent_setup			; for CCR mode (required to have better gas working)
-	btfsc	FLAG_ccr_mode				; =1: CCR mode (fixed ppO2 or Sensor) active
-	bra		diveloop_boot_3
-	btfsc	FLAG_pscr_mode
-	bra		diveloop_boot_3
-	bcf		FLAG_diluent_setup			; for OC mode (required to have better gas working)
 diveloop_boot_3:
 	bcf		LEDg						; switch off green LED / release reset to RX circuitry
 	bcf		LEDr						; switch off red   LED
-	bcf		realdive
-	btfss	simulatormode_active		; in simulator mode?
+	btfss	sensor_override_active		; in simulator mode?
 	call	disable_rs232				; NO - disable RS232
 IFDEF _screendump
-	btfsc	enable_screen_dumps			; =1: ignore vin_usb, wait for "l" command (screen dump)
+	btfsc	screen_dump_avail			; screen dump function enabled?
-	call	enable_rs232				; also sets to speed_normal
+	call	enable_rs232				; enable interface (also sets CPU speed to normal)
 ENDIF
-	; reset dive time seconds
+	clrf	apnoe_surface_mins			; clear apnoe surface time, minutes (8 bit)
-;	movlw	.2							; start at 2 seconds
+	clrf	apnoe_surface_secs			; clear apnoe surface time, seconds (8 bit)
-;	movwf	total_divetime_seconds+0
+	clrf	apnoe_dive_mins				; clear apnoe dive    time, minutes (8 bit)
-;	clrf	total_divetime_seconds+1
+	clrf	apnoe_dive_secs				; clear apnoe dive    time, seconds (8 bit)
-;	movwf	divesecs
-;	movwf	apnoe_secs
-;	bsf		divemode2					; displayed dive time is running (dive time starts HERE)
-	; clear the timers (start dive times at zero)
-	clrf	total_divetime_seconds+0
-	clrf	total_divetime_seconds+1
-	clrf	divesecs
-	clrf	divemins+0
-	clrf	divemins+1
-	clrf	apnoe_secs
-	clrf	apnoe_mins
-	; divemode2 flag will be set by pressure & timeout evaluation in function set_dive_modes
 	return								; done with dive mode boot
 ;=============================================================================
-divemode_check_for_warnings:
+divemode_check_warnings:
 	movlw	.1							; one message at a time in alternative layout
-	btfss	alternative_divelayout
+	btfss	alt_layout_active			; in alternative layout?
-	movlw	.2							; two messages at a time in default layout
+	movlw	.2							; NO - two messages at a time in normal layout
-	cpfsgt	message_counter				; only one (or two) messages active?
+	cpfsgt	message_counter				; more than one (alt layout) / 2 (normal layout) messages currently active?
-	bra		divemode_check_for_warnings1; YES - update every second
+	bra		divemode_check_warnings1	; NO  - update messages every second
-	btfss	secs,0						; every two seconds...
+;										; YES - update every 4 seconds:
-	return
+;	btfss	timebase_1sec				      - on second 1 or 3 ?
-	btfss	secs,1						; every four seconds...
+;	return								;       NO  - no update in this cycle
-	return
+;	btfss	timebase_2sec				;       YES - on second 3 ?
+;	return								;             NO  - no update in this cycle
-divemode_check_for_warnings1:
+;	;bra	divemode_check_warnings1	;             YES - update messages
+										; NO  - update every 2 seconds
+	btfsc	timebase_1sec				;     - on even second?
+	return								;       NO  - done
+	;bra	divemode_check_warnings1	;       YES - update messages
+divemode_check_warnings1:
+	; start a new message collection cycle
 	bcf		message_advice				; clear flag for messages of level advice
 	bcf		message_attention			; clear flag for messages of level attention
 	bcf		message_warning				; clear flag for messages of level warning
 	clrf	message_counter				; clear message counter
 	; messages sorted by severity: highest severity warnings first, then attentions, advices and last info
 	; warnings for all modes
 	call	check_warn_battery			; check if the battery level should be displayed/warned
+	rcall	check_depth_limit			; check current depth against set depth limit
 	call	check_divetimeout			; check and show the dive mode timeout (not actually a warning)
-	btfsc	FLAG_apnoe_mode				; in Apnoe mode?
+	btfsc	FLAG_apnoe_mode				; in apnoe mode?
-	bra		divemode_check_for_warnings2; YES
+	bra		divemode_check_warnings2	; YES
 	btfsc	FLAG_gauge_mode				; in gauge mode?
-	bra		divemode_check_for_warnings2; YES
+	bra		divemode_check_warnings2	; YES
 	; warnings applicable only in deco modes
 	rcall	check_ppO2					; check ppO2 and displays warning, if required
-	btfss	sensors_agree				; are the sensor values within the threshold range?
+IFDEF _external_sensor
-	rcall	check_warn_sensors_disagree	; NO  - further evaluate
+	btfss	o2_sensors_agree			; are the sensor values within the threshold range?
-	btfsc	sensors_agree				; are the sensor values within the threshold range?
+	rcall	check_warn_sensors_disagree	; NO  - do further evaluation
-	bcf		sensor_warning				; YES - revoke memorized sensor warning
+	btfsc	o2_sensors_agree			; are the sensor values within the threshold range?
+	bcf		o2_sensors_warning			; YES - clear flag for a new warning
+ENDIF
 	rcall	check_outside				; check of ZHL16 model violation
+IFDEF _helium
 	rcall	check_IBCD					; check for IBCD attention or warning
+ENDIF
-	rcall	check_OC_gas_avail			; check if a breathable OC gas is available
+	btfsc	FLAG_ccr_mode				; in CCR mode?
+	rcall	check_OC_gas_avail			; YES - check if a breathable OC (bailout) gas is available
+	btfsc	FLAG_pscr_mode				; in pSCR mode?
+	rcall	check_OC_gas_avail			; YES - check if a breathable OC (bailout) gas is available
 	btfsc	decostop_active				; in deco mode?
-	rcall	check_and_store_gf_violation; YES - sets warnings, if required
+	rcall	check_and_store_sat_violation; YES - sets warnings, if required
 	rcall	check_mbubbles				; check for micro bubbles
+	rcall	check_cns_violation			; check CNS value and display it, if required
-	rcall	check_cns_violation			; Check CNS value and display it, if required
 	rcall	check_gas_needs_ascent		; show gas needs warning if any gas need for ascent is > threshold
 	rcall	check_eod_cns_violation		; check CNS values for end-of-dive and display warning, if required
 	rcall	check_display_ftts			; show @+x time
 IFDEF _cave_mode
-	btfsc	FLAG_cave_mode				; cave mode enabled?
+	btfsc	cave_mode					; cave mode switched on?
 	rcall	check_cavemode				; YES - check cave mode status
 ENDIF
-	btfsc	use_agf						; in aGF mode?
+	btfsc	use_aGF						; using alternative GF factors?
 	rcall	warn_agf					; YES - show memo
-	btfsc	setpoint_fallback			; fallback to SP1 due to external O2 sensor failure?
+	btfsc	sp_fallback					; in fallback condition due to O2 sensor failure?
 	rcall	warn_fallback				; YES - show a warning
 	btfsc	better_dil_available		; is a better diluent available?
 	rcall	advice_gas_change			; YES - display an advice
 	btfsc	better_gas_available		; is a better gas     available?
 	rcall	advice_gas_change			; YES - display an advice
-divemode_check_for_warnings2:
+divemode_check_warnings2:
 IFDEF _rx_functions
-	btfss	FLAG_tr_enabled					; TR functions enabled?
+	btfss	tr_functions_activated		; TR functions activated?
-	bra		divemode_check_for_warnings3	; NO  - skip
+	bra		divemode_check_warnings3	; NO  - skip
-	call	check_tr_functions				; YES - check transmitter functions
+	call	check_tr_functions			; YES - check transmitter functions
-	call	check_tr_messages				;     - check SAC attention and switch advice
+	call	check_tr_messages			;     - check SAC attention and switch advice
 ENDIF
-divemode_check_for_warnings3:
+divemode_check_warnings3:
-	; Display the attention or warning icon?
+	; Display / clear the advice, attention or warning icon
-	btfsc	message_advice					; any message of level advice?
+	btfsc	message_advice				; any message of level advice?
-	bsf		FLAG_TFT_divemode_warning		; YES
+	bsf		FLAG_TFT_sign_show			; YES
-	btfsc	message_attention				; any message of level attention?
+	btfsc	message_attention			; any message of level attention?
-	bsf		FLAG_TFT_divemode_warning		; YES
+	bsf		FLAG_TFT_sign_show			; YES
-	btfsc	message_warning					; any message of level warning?
+	btfsc	message_warning				; any message of level warning?
-	bsf		FLAG_TFT_divemode_warning		; YES
+	bsf		FLAG_TFT_sign_show			; YES
-	btfss	FLAG_TFT_divemode_warning		; any message of above levels?
+	btfss	FLAG_TFT_sign_show			; any message of above levels?
-	bsf		FLAG_TFT_divemode_warning_clear ; NO - clear warning icon
+	bsf		FLAG_TFT_sign_clear 		; NO - clear sign
-	; Setup message page number
+	; Increment message page number
-	incf	message_page,F
+	incf	message_page,F				; increment page number
-	movf	message_page,W
+	bcf		STATUS,C					; clear carry bit
-	bcf		STATUS,C
+	movf	message_page,W				; get page number into WREG
-	btfss	alternative_divelayout			; in alternative layout?
+	btfss	alt_layout_active			; in alternative layout?
-	rlcf	message_page,W					; NO - *2
+	rlcf	WREG,W						; NO - each page can take two messages
-	cpfsgt	message_counter					; > message_counter?
+	cpfsgt	message_counter				; number of actual messages > message capacity ?
-	clrf	message_page					; NO - clear
+	clrf	message_page				; NO - all messages could be shown, restart from first page next time
 	; Clear both rows of messages if there is nothing to show at all
-	tstfsz	message_counter					; any messages?
+	tstfsz	message_counter				; any message to show?
-	bra		divemode_check_for_warnings4	; YES - look if second row needs to be cleared
+	bra		divemode_check_warnings4	; YES - look if second row needs to be cleared
-	bsf		FLAG_TFT_dive_warning_text_clear; set flag
+	bsf		FLAG_TFT_message_clear_both	; NO  - request clearing of left-over messages
-	return
+	return								;     - done
-divemode_check_for_warnings4:
+divemode_check_warnings4:
 	; Clear 2nd row of messages if there is nothing to show (on this page)
-	btfss	second_row_warning				; =1: the second row contains a warning
+	btfss	message_2nd_row_used		; does the 2nd row contain a message?
-	bsf		FLAG_TFT_dive_warning_text_clr2	; set flag for 2nd row
+	bsf		FLAG_TFT_message_clear_2nd	; NO - set flag to clear the 2nd row
-	return									; done
+	return								; done
+;-----------------------------------------------------------------------------
 	global	check_warn_battery
 check_warn_battery:
-	movff	batt_percent,lo
+	movff	batt_percent,lo				; get battery %
-	movlw	battery_show_level+1
+	movlw	battery_show_level+1		; get threshold for showing battery level, incremented by 1
 	cpfslt	lo							; battery percentage ok?
 	return								; YES - no display, no warning
 	; Display Battery, but warn?
-	movff	batt_percent,lo
+	movff	batt_percent,lo				; get battery %
-	movlw	color_code_battery_low+1
+	movlw	color_code_battery_low+1	; get threshold for battery warning, incremented by 1
 	cpfsgt	lo							; battery percent below warning threshold?
 	bsf		message_warning				; YES - set warning flag
-	btfsc	alternative_divelayout		; in alternative layout?
+	movlw	index_clock_batt_surfpress	; index of custom view clock, battery and surface pressure
-	bra		check_warn_battery2			; YES - show warning
+	cpfseq	active_customview			; battery shown in custom view?
-	movlw	index_clock_batt_surfpress	; NO  - index of custom view clock, battery and surface pressure
+	bra		check_warn_battery2			; NO  - show warning
-	cpfseq	menupos3					;     - battery shown in custom view?
+	return								; YES - do not show twice (in custom view and in message area)
-	bra		check_warn_battery2			;       NO  - show warning
-	return								;       YES - do not show twice (in custom view and in message area)
 check_warn_battery2:
 	incf	message_counter,F			;       increase counter
-	goto	TFT_update_batt_percent_divemode ;  show percent (and return)
+	goto	TFT_msg_batt_percent_divemode ;  show percent (and return)
 check_divetimeout:
-	btfsc	divemode2					; dive time running?
+	btfsc	count_divetime				; is dive time counted?
 	return								; YES - do nothing
 	incf	message_counter,F			; increase counter
 	goto	TFT_divetimeout				; show timeout counter (and return)
 check_ppO2:
+IFDEF _ccr_pscr
 	btfsc	FLAG_oc_mode				; are we in OC mode?
 	bra		check_ppO2_1				; YES - continue with breathed gas
-	btfsc	FLAG_bailout_mode			; NO  - in bailout?
+	btfsc	bailout_mode				; NO  - in bailout?
 	bra		check_ppO2_1				;       YES - continue with breathed gas
 	; CCR / pSCR mode - checks on pure diluent
-	movff	int_O_pure_ppO2+0,lo		; get value and attention/warning flags for the pure diluent
+	MOVII	int_O_pure_ppO2,mpr			; get value and attention/warning flags for the pure diluent
-	movff	int_O_pure_ppO2+1,hi		;
+	btfsc	hi,int_warning_flag			; is there a ppO2 low or high warning on the pure diluent?
-	btfsc	hi,int_warning_flag			; ppO2 of the pure diluent to low or high?
 	rcall	check_ppO2_dw				; YES - show warning and return on next line
 	btfsc	hi,int_attention_flag		; ppO2 of the pure diluent in attention state?
 	rcall	check_ppO2_da				; YES - show attention and return on next line
+ENDIF
 	; all modes - checks on breathed gas (OC or from loop)
 check_ppO2_1:
-	movff	int_O_breathed_ppO2+0,lo	; get value and attention/warning flags for the breathed gas
+	MOVII	int_O_breathed_ppO2,mpr		; get value and attention/warning flags for the breathed gas
-	movff	int_O_breathed_ppO2+1,hi	; get warnings for breathed gas
 	btfsc	hi,int_attention_flag		; breathed ppO2 in attention state (when in loop mode, no attention will be generated)?
 	bra		check_ppo2_display_a		; YES - set attention flag and show ppO2
-	btfsc	hi,int_low_flag				; breathed ppO2 to low?
+	btfsc	hi,int_low_flag				; breathed ppO2 too low?
 	bra		check_ppO2_low				; YES - record the warning and show ppO2
-	btfsc	hi,int_high_flag			; breathed ppO2 to high?
+	btfsc	hi,int_high_flag			; breathed ppO2 too high?
 	bra		check_ppO2_high				; YES - record the warning and show ppO2
 	TSTOSS	opt_showppo2				; show ppO2 anyhow? (0 = no, 1 = show always)
 	return								; NO  - no warnings, no show - done
 	bra		check_ppO2_common_2			; YES - but only when in OC or bailout...
 check_ppO2_low:
 	movlw	d'4'						; set type of alarm (ppO2 low)
 	bra		check_ppO2_common			; continue with common part
 check_ppO2_high:
 	movlw	d'5'						; set type of alarm (ppO2 high)
 check_ppO2_common:
-	movwf	AlarmType					; copy alarm type to alarm register
+	movwf	alarm_type					; copy alarm type to alarm register
 	bsf		event_occured				; set event   flag
 	bsf		message_warning				; show warning sign
 check_ppO2_common_2:
 	btfsc	FLAG_oc_mode				; are we in OC mode?
-	bra		check_ppo2_display			; YES
+	bra		check_ppo2_display			; YES - show
-	btfsc	FLAG_bailout_mode			; are we in bailout mode?
+	btfsc	bailout_mode				; are we in bailout mode?
-	bra		check_ppo2_display			; YES
+	bra		check_ppo2_display			; YES - show
 	return								; NO  - in loop mode, ppO2 is already shown via setpoint display
 check_ppo2_display_a:
 	bsf		message_attention			; show attention sign
 check_ppo2_display:
-	btfsc	alternative_divelayout		; in alternative layout?
+	movlw	index_ppo2_ead_end_cns		; index of custom view ppO2, EAD/END and CNS)
-	bra		check_ppO2_d				; YES - show warning
+	cpfseq	active_customview			; ppO2 shown?
-	movlw	index_ppo2_ead_end_cns		; NO  - index of custom view ppO2, EAD/END and CNS)
+	bra		check_ppO2_b				; NO
-	cpfseq	menupos3					;       ppO2 shown?
+	return								; YES - do not show twice (in custom view and in warning area)
-	bra		check_ppO2_b				;       NO
-	return								;       YES - do not show twice (in custom view and in warning area)
 check_ppO2_b:
 	movlw	index_pscr_info				; index of custom view with pSCR data
-	cpfseq	menupos3					; ppO2 shown?
+	cpfseq	active_customview			; ppO2 shown?
-	bra		check_ppO2_d				; NO  - show warning
+	bra		check_ppO2_d				; NO  - show ppO2
 	return								; YES - do not show twice (in custom view and in warning area)
 check_ppO2_dw:
 	bsf		message_warning				; show warning sign
 check_ppO2_da:
 	bsf		message_attention			; show attention sign (no problem if a warning sign is set as well, as it will take priority)
 check_ppO2_d:
 	incf	message_counter,F			; increase counter
-	goto	TFT_display_ppo2_warning	; show breathed gas or diluent ppO2 warning (and return)
+	goto	TFT_show_ppo2_warning		; show breathed gas or diluent ppO2 warning (and return)
 check_display_ftts:
-	movff	char_I_extra_time,lo		; get extra time
+	btfss	count_divetime				; is dive time counted?
-	tstfsz	lo							; extra time > 0 ?
+	return								; NO  - omit
-	bra		check_display_ftts_1		; YES - continue checking bailout condition
+	movff	char_I_extra_time,lo		; YES - get extra time
-	return								; NO  - done
+	tstfsz	lo							;     - extra time > 0 ?
+	bra		check_display_ftts_1		;       YES - continue checking bailout condition
+	return								;       NO  - done
 check_display_ftts_1:
-	btfsc	FLAG_bailout_mode			; in bailout mode?
+	btfsc	bailout_mode				; in bailout mode?
 	return								; YES - in bailout no fTTS will be computed, so nothing to display
 	incf	message_counter,F			; NO  - increase counter
-	goto	TFT_display_ftts			;     - show @+x time
+	goto	TFT_show_ftts				;     - show @+x time
 	global	check_cns_violation
 check_cns_violation:
 	; Check if CNS should be displayed
-	movff	int_O_CNS_fraction+1,WREG	; get high byte
+	movff	int_O_CNS_current+1,WREG	; get current CNS, high byte
 	btfsc	WREG,int_warning_flag		; warning flag set?
 	bra		check_cns_violation_1		; YES - issue warning
 	btfsc	WREG,int_attention_flag		; NO  - attention flag set?
 	bra		check_cns_violation_2		;       YES - issue attention
 	return								;       NO  - done
 check_cns_violation_1:
 	bsf		message_warning				; show warning sign
 check_cns_violation_2:
 	bsf		message_attention			; show attention sign
-	btfsc	alternative_divelayout		; in alternative layout?
+	movlw	index_ppo2_ead_end_cns		; index of custom view ppO2, EAD/END and CNS
-	bra		check_cns_violation_4		; YES - show attention
+	cpfseq	active_customview			; CNS shown?
-	movlw	index_ppo2_ead_end_cns		; NO  - index of custom view ppO2, EAD/END and CNS
+	bra		check_cns_violation_3		; NO
-	cpfseq	menupos3					;     - CNS shown?
+	return								; YES - do not show twice (in custom view and in warning area)
-	bra		check_cns_violation_3		;       NO
-	return								;       YES - do not show twice (in custom view and in warning area)
 check_cns_violation_3:
 	movlw	index_CNS					; index of custom view with CNS values
-	cpfseq	menupos3					; CNS shown?
+	cpfseq	active_customview			; CNS shown?
 	bra		check_cns_violation_4		; NO
 	return								; YES - do not show twice (in custom view and in warning area)
 check_cns_violation_4:
 	incf	message_counter,F			; increase counter
-	goto	TFT_display_cns				; show CNS (and return)
+	goto	TFT_show_cns				; show CNS (and return)
 	global	check_eod_cns_violation		; check end-of-dive CNS values
 check_eod_cns_violation:
-	movff	int_O_CNS_fraction+1,WREG	; get high-byte of current CNS value
+	movff	int_O_CNS_current+1,WREG	; get current CNS, high byte
 	btfsc	WREG,int_warning_flag		; current CNS value in warning state?
 	return								; YES - inhibit end-of-dive warning if current CNS is already in warning
-	movff	int_O_normal_CNS_fraction+1,WREG
+	movff	int_O_CNS_norm+1,WREG		; get CNS at end of dive in normal plan, high byte
 	btfsc	WREG,int_invalid_flag		; flag for invalid value set?
 	bra		check_eod_cns_violation1	; YES - continue with checking the other CNS value
 	btfsc	WREG,int_warning_flag		; NO  - flag for warning set?
 	bra		check_eod_cns_violation2	;       YES - issue warning
 check_eod_cns_violation1:				;       NO  - continue with checking the other CNS value
-	movff	int_O_alternate_CNS_fraction+1,WREG
+	movff	int_O_CNS_alt+1,WREG		; get CNS at end of dive in alternative plan, high byte
 	btfsc	WREG,int_invalid_flag		; flag for invalid value set?
 	return								; YES - done with CNS checking
 	btfsc	WREG,int_warning_flag		; NO  - flag for warning set?
 	bra		check_eod_cns_violation2	;       YES - issue warning
 	return								;       NO  - done with CNS checking
 check_eod_cns_violation2:				; issue warning (actually only on attention level)
 	bsf		message_attention			; show attention sign
-	btfsc	alternative_divelayout		; in alternative layout?
+	movlw	index_CNS					; index of custom view with CNS values
-	bra		display_eod_cns_violation	; YES - show warning
+	cpfseq	active_customview			; CNS values shown?
-	movlw	index_CNS					; NO  - index of custom view with CNS values
+	bra		display_eod_cns_violation	; NO  - issue textual warning
-	cpfseq	menupos3					;     - CNS values shown?
+	return								; YES - do not show twice (in custom view and in warning area)
-	bra		display_eod_cns_violation	;       NO  - issue textual warning
-	return								;       YES - do not show twice (in custom view and in warning area)
 display_eod_cns_violation:
 	incf	message_counter,F			; increase counter
-	goto	TFT_display_eod_cns			; issue CNS at end-of-dive warning (and return)
+	goto	TFT_warning_eod_cns			; issue CNS at end-of-dive warning (and return)
-	global	check_and_store_gf_violation
+	global	check_and_store_sat_violation
-check_and_store_gf_violation:
+check_and_store_sat_violation:
-	movff	int_O_gradient_factor+1,WREG	; get upper byte of gradient factor
+	movff	int_O_lead_supersat+1,WREG		; get upper byte of leading tissue's supersaturation
 	btfss	WREG,int_warning_flag			; check if the warning flag is set
-	bra		check_and_store_gf_violation2	; NO  - continue with checking for attention flag
+	bra		check_and_store_sat_violation2	; NO  - continue with checking for attention flag
 	movlw	d'2'							; YES - set type of alarm
-	movwf	AlarmType						;		copy to alarm register
+	movwf	alarm_type						;     - copy to alarm register
-	bsf		event_occured					;		set event   flag
+	bsf		event_occured					;     - set event   flag
-	bsf		message_warning					;		set warning flag
+	bsf		message_warning					;     - set warning flag
-	bra		check_and_store_gf_violation3	;		show gf warning
+	bra		check_and_store_sat_violation3	;     - show GF warning
-check_and_store_gf_violation2:
+check_and_store_sat_violation2:
 	btfsc	WREG,int_attention_flag			; check if the attention flag is set
-	bra		check_and_store_gf_violation3	; YES - show gf
+	bra		check_and_store_sat_violation3	; YES - show gf
 	TSTOSS	opt_enable_IBCD					; NO  - IBCD warning activated?
-	bra		check_and_store_gf_violation4	;		NO  - continue checking of deco info
+	bra		check_and_store_sat_violation4	;       NO  - continue checking of deco info
-	movff	char_O_deco_warnings,WREG		;		YES - get the deco warnings vector
+	movff	char_O_deco_warnings,WREG		;       YES - get the deco warnings vector
-	btfss	WREG,IBCD_warning				;			 is the IBCD warning flag set?
+	btfss	WREG,IBCD_warning				;           - is the IBCD warning flag set?
-	bra		check_and_store_gf_violation4	;			 NO  - continue checking for deco info
+	bra		check_and_store_sat_violation4	;             NO  - continue checking for deco info
-check_and_store_gf_violation3:				;			 YES - show gf
+check_and_store_sat_violation3:				;             YES - show GF
 	bsf		message_attention				; show attention sign
 	incf	message_counter,F				; increase counter
-	goto	TFT_warning_gf					; show GF (and return)
+	goto	TFT_warning_sat					; show saturation (and return)
-check_and_store_gf_violation4:				; check for deco info
+check_and_store_sat_violation4:				; check for deco info
 	btfss	divemode						; in dive mode?
 	return									; NO  - done, return
-	btfsc	FLAG_bailout_mode				; YES - in bailout mode?
+	btfsc	bailout_mode					; YES - in bailout mode?
-	return									;       YES - done, return (deco_decreasing flag is not updated when in bailout mode)
+	return									;       YES - done, return (deco zone flag is not updated when in bailout mode)
 	movff	char_O_deco_info,WREG			;       NO  - get the deco info vector
-	btfss	WREG,deco_decreasing			;             check if the deco_decreasing flag is set
+	btfss	WREG,deco_zone					;             check if the deco zone flag is set
 	return									;             NO  - done, return
 	incf	message_counter,F				;             YES - increase counter
 	goto	TFT_info_deco					;                 - show deco info
+check_depth_limit:
+	bcf		depth_limit_exceeded		; clear warning flag by default
+	movff	opt_max_depth,WREG			; get depth limit
+	cpfsgt	depth_meter					; current depth > depth limit?
+	return								; NO
+	bsf		depth_limit_exceeded		; YES - set warning flag
+	incf	message_counter,F			;     - increase counter
+	bsf		message_warning				;     - set warning flag
+	goto	TFT_warning_depth			;     - show warning
 check_outside:
 	movff	char_O_deco_warnings,WREG	; bank-safe copy of deco warnings
 	btfss	WREG,outside_warning_lock	; are we outside of the ZH-L16 model?
 	goto	TFT_warning_mbubbles		; show micro bubbles warning (and return)
 IFDEF _cave_mode
 check_cavemode:
 	incf	message_counter,F			; increase counter
-	btfsc	FLAG_dive_turned			; dive turned?
+	btfsc	dive_turned					; dive turned?
 	goto	TFT_info_dive_turned		; YES - show info that dive is turned
-	btfsc	FLAG_cave_mode_shutdown		; NO  - has cave mode shut down?
+	btfsc	FLAG_backtrack_full			; NO  - is the backtracking storage full?
 	goto	TFT_warn_cave_shutdown		;       YES - show that cave mode has shut down
 	goto	TFT_info_cave_mode			;       NO  - show that cave mode is active
 ENDIF
 warn_agf:
 	incf	message_counter,F			; increase counter
-	goto	TFT_warning_agf				; show aGF warning (and return)
+	goto	TFT_warning_agf				; show aGF reminder (and return)
 warn_fallback:
 	incf	message_counter,F			; increase counter
 	bsf		message_warning				; set warning flag
 	goto	TFT_warning_fallback		; show fallback warning (and return)
+;=============================================================================
 IFDEF _rx_functions
 check_tr_messages:
-	movff	int_O_sac_rate+1,WREG		; bank-safe copy of current SAC rate
+	btfss	count_divetime				; is the dive time counted, i.e. deeper than dive threshold?
-	btfss	WREG,int_attention_flag		; attention flag set?
+	return								; NO  - suppress messages
-	bra		check_tr_messages2			; NO  - skip
+	movff	int_O_SAC_measured+1,WREG	; YES - bank-safe copy of measured SAC rate
-	btfsc	WREG,int_not_avail_flag		; SAC rate available?
+	btfss	WREG,int_attention_flag		;     - attention flag set?
-	bra		check_tr_messages2			; NO  - continue with swap advice
+	bra		check_tr_messages2			;       NO  - skip
-	bsf		message_attention			; YES - show attention sign
+	btfsc	WREG,int_not_avail_flag		;       SAC rate available?
-	btfsc	alternative_divelayout		;     - in alternative layout?
+	bra		check_tr_messages2			;       NO  - continue with swap advice
-	bra		check_tr_messages1			;       YES - show attention message
+	bsf		message_attention			;       YES - show attention sign
-	movlw	index_pressures_SAC			;       NO  - index of custom view with SAC rate
+	movlw	index_pressures_SAC			;           - index of custom view with SAC rate
-	cpfseq	menupos3					;           - SAC rate shown right now?
+	cpfseq	active_customview			;           - SAC rate shown right now?
 	bra		check_tr_messages1			;             NO  - show attention message
 	bra		check_tr_messages2			;             YES - do not show twice, continue with swap advice
 check_tr_messages1:
 	incf	message_counter,F			; increase counter
 	call	TFT_attention_sac			; show SAC attention
 	incf	message_counter,F			; YES - increase counter
 	bsf		message_advice				;     - show advice sign
 	goto	TFT_advice_switch			;     - show swap advice
-#DEFINE show_custview			ul,0		; show pressure readings custom view
-#DEFINE show_transmitter		ul,1		; show transmitter attention
-#DEFINE show_pres_warning		ul,2		; show transmitter pressure warning
-#DEFINE show_pres_attention		ul,3		; show transmitter pressure attention
 check_tr_functions:
-	clrf	ul								; set all messages as not shown yet
+	clrf	xmitter_flags_mesg				; set all messages as not shown yet
-	btfsc	alternative_divelayout			; in alternative layout?
+	movlw	index_pressures_SAC				; index of custom view pressure readings
-	bra		check_tr_functions_tr1			; YES - continue with checking transmitter 1
+	cpfseq	active_customview				; pressure readings shown?
-	movlw	index_pressures_SAC				; NO  - index of custom view pressure readings
+	bra		check_tr_functions_tr1			; NO  - continue with checking transmitter 1
-	cpfseq	menupos3						;     - pressure readings shown?
+	bsf		pres_customview_shown			; YES - suppress redraw by faking it has already been redrawn
-	bra		check_tr_functions_tr1			;       NO  - continue with checking transmitter 1
-	bsf		show_custview					;       YES - suppress redraw by faking it has already been redrawn
 check_tr_functions_tr1:
 	movff	char_I_pressure_stat+0,WREG		; get status of 1st pressure reading
 	rcall	check_tr_functions_helper1		; check for transmitter 1 lost
 	rcall	check_tr_functions_helper2		; check for transmitter 1 low battery
 	movff	int_IO_pressure_value+1,WREG	; get high byte of 1st pressure reading
 	rcall	check_tr_functions_helper6		; check for transmitter 2 low battery
 	movff	int_IO_pressure_value+3,WREG	; get high byte of 2nd pressure reading
 	rcall	check_tr_functions_helper7		; check for transmitter 2 pressure warning
 	rcall	check_tr_functions_helper8		; check for transmitter 2 pressure attention
 check_tr_functions_show_xmtr:
-	btfss	show_transmitter				; shall show transmitter message?
+	btfss	show_transmitter_attention		; shall show transmitter message?
 	bra		check_tr_functions_show_warn	; NO  - continue with pressure warning
 	bsf		message_attention				; YES - set flag for attention
 	incf	message_counter,F				;     - increase counter
 	call	TFT_attention_transmitter		;     - show transmitter attention message
 check_tr_functions_show_warn:
 	btfsc	WREG,char_transmitter_lost		; transmitter 1 lost?
 	bra		check_tr_functions_helper1a		; YES - show transmitter attention message
 	bcf		transmitter1_lost				; NO  - clear flag for old lost attention
 	return									;     - done
 check_tr_functions_helper1a:
-	bsf		show_transmitter				; show transmitter attention
+	bsf		show_transmitter_attention		; show transmitter attention
 	btfsc	transmitter1_lost				; is it a new message?
 	return									; NO  - do not show the pressure readings custom view again
 	bsf		transmitter1_lost				; YES - memorize it's an old message now
 	bra		check_tr_functions_show_cv		;     - show custom view
 	btfsc	WREG,char_transmitter_low_bat	; transmitter 1 low battery?
 	bra		check_tr_functions_helper2a		; YES - show transmitter attention message
 	bcf		transmitter1_battery			; NO  - clear flag for old battery attention
 	return									;     - done
 check_tr_functions_helper2a:
-	bsf		show_transmitter				; show transmitter attention
+	bsf		show_transmitter_attention		; show transmitter attention
 	btfsc	transmitter1_battery			; is it a new message?
 	return									; NO  - do not show the pressure readings custom view again
 	bsf		transmitter1_battery			; YES - memorize it's an old message now
 	bra		check_tr_functions_show_cv		;     - show custom view
 	btfsc	WREG,char_transmitter_lost		; transmitter 2 lost?
 	bra		check_tr_functions_helper5a		; YES - show transmitter attention message
 	bcf		transmitter2_lost				; NO  - clear flag for old lost attention
 	return									;     - done
 check_tr_functions_helper5a:
-	bsf		show_transmitter				; show transmitter attention
+	bsf		show_transmitter_attention		; show transmitter attention
 	btfsc	transmitter2_lost				; is it a new message?
 	return									; NO  - do not show the pressure readings custom view again
 	bsf		transmitter2_lost				; YES - memorize it's an old message now
 	bra		check_tr_functions_show_cv		;     - show custom view
 	btfsc	WREG,char_transmitter_low_bat	; transmitter 2 low battery?
 	bra		check_tr_functions_helper6a		; YES - show transmitter attention message
 	bcf		transmitter2_battery			; NO  - clear flag for old battery attention
 	return									;     - done
 check_tr_functions_helper6a:
-	bsf		show_transmitter				; show transmitter attention
+	bsf		show_transmitter_attention		; show transmitter attention
 	btfsc	transmitter2_battery			; is it a new message?
 	return									; NO  - do not show the pressure readings custom view again
 	bsf		transmitter2_battery			; YES - memorize it's an old message now
 	bra		check_tr_functions_show_cv		;     - show custom view
 	return									; NO  - do not show the pressure readings custom view again
 	bsf		transmitter2_pres_att			; YES - memorize it's an old message now
 	;bra	check_tr_functions_show_cv		;     - show custom view
 check_tr_functions_show_cv:
-	btfsc	show_custview					; is the pressure readings custom view not shown yet shown?
+	btfsc	pres_customview_shown			; is the pressure readings custom view not shown yet?
 	return									; NO  - already shown, done
-	bsf		show_custview					; YES - mark as shown
+	bsf		pres_customview_shown			; YES - mark as shown
-	btfsc	alternative_divelayout			;     - in alternative layout?
+	movlw	index_pressures_SAC-1			;     - custom view number one below pressure readings
-	call	switch_layout_to_normal			;       YES - switch to normal layout
+	movwf	active_customview				;     - set custom view number
-	movlw	index_pressures_SAC-1			;       custom view number one below pressure readings
+	bsf		request_next_custview			;     - initiate toggle to desired custom view -> pressure readings view will be shown
-	movwf	menupos3						;       set custom view number
+	return									;     - done
-	bsf		toggle_customview				;       initiate toggle to desired custom view ->  pressure readings view will be shown
-	return									;       done
+ENDIF
-ENDIF
+;=============================================================================
 check_gas_needs_ascent:
-	banksel	int_O_ascent_pres_need
+	banksel	int_O_gas_need_pres
-	movf	int_O_ascent_pres_need+1,w	; get               high byte from pres need of 1st tank
+	movf	int_O_gas_need_pres+1,W		; get               high byte from pres need of 1st tank
-	iorwf	int_O_ascent_pres_need+3,w	; inclusive or with high byte from pres need of 2nd tank
+	iorwf	int_O_gas_need_pres+3,W		; inclusive or with high byte from pres need of 2nd tank
-	iorwf	int_O_ascent_pres_need+5,w	; inclusive or with high byte from pres need of 3rd tank
+	iorwf	int_O_gas_need_pres+5,W		; inclusive or with high byte from pres need of 3rd tank
-	iorwf	int_O_ascent_pres_need+7,w	; inclusive or with high byte from pres need of 4th tank
+	iorwf	int_O_gas_need_pres+7,W		; inclusive or with high byte from pres need of 4th tank
-	iorwf	int_O_ascent_pres_need+9,w	; inclusive or with high byte from pres need of 5th tank
+	iorwf	int_O_gas_need_pres+9,W		; inclusive or with high byte from pres need of 5th tank
 	banksel	common
 	btfsc	WREG,int_invalid_flag		; check if invalid flag is set
 	return								; YES - no further checking required
-	btfsc	WREG,int_warning_flag		; check if any gas has a pres_need >= pres_fill
+	btfsc	WREG,int_warning_flag		; NO  - check if any gas has a pres_need >= pres_fill
-	bsf		message_warning				; YES - set warning flag
+	bra		check_gas_needs_ascent_warn	;       YES - generate a warning
-	btfsc	WREG,int_warning_flag		; check if any gas has a pres_need >= pres_fill
+	btfsc	WREG,int_attention_flag		;       NO  - check if any gas has a pres_need >= pres_fill * threshold
-	goto	TFT_warning_gas_needs_warn	; Yes - show a warning
+	bra		check_gas_needs_ascent_att	;             YES - generate an attention
-	btfsc	WREG,int_attention_flag		; check if any gas has a pres_need >= pres_fill * threshold
+	bcf		gas_needs_attention			;             NO  - clear flag for a new attention
-	bsf		message_attention			; YES - set attention flag
+	bcf		gas_needs_warning			;                 - clear flag for a new warning
-	btfsc	WREG,int_attention_flag		; check if any gas has a pres_need >= pres_fill * threshold
+	return								;                 - done
-	goto	TFT_warning_gas_needs_att	; YES - show an attention
-	bcf		gas_needs_attention			; NO  - clear flag for a new attention
+check_gas_needs_ascent_warn:
-	bcf		gas_needs_warning			;       clear flag for a new warning
+	bsf		message_warning				; set warning flag
-	return
+	incf	message_counter,F			; increase counter
+	btfsc	gas_needs_warning			; is it a new warning?
+	goto	TFT_warning_gas_needs_warn	; NO  - do not show the gas needs custom view again
+	bsf		gas_needs_warning			; YES - memorize it's an old now
+	movlw	index_gas_needs_ascent-1	;     - custom view number one below gas needs view
+	movwf	active_customview			;     - set custom view number
+	bsf		request_next_custview		;     - initiate toggle to desired custom view -> gas needs view will be shown
+	goto	TFT_warning_gas_needs_warn	;     - show warning message
+check_gas_needs_ascent_att:
+	bsf		message_attention			; set attention flag
+	incf	message_counter,F			; increase counter
+	btfsc	gas_needs_attention			; is it a new attention?
+	goto	TFT_warning_gas_needs_att	; NO  - do not show the gas needs custom view again
+	bsf		gas_needs_attention			; YES - memorize it's an old now
+	movlw	index_gas_needs_ascent-1	;     - custom view number one below gas needs view
+	movwf	active_customview			;     - set custom view number
+	bsf		request_next_custview		;     - initiate toggle to desired custom view -> gas needs view will be shown
+	goto	TFT_warning_gas_needs_att	;     - show attention message
+;=============================================================================
+IFDEF _external_sensor
 check_warn_sensors_disagree:
 	incf	message_counter,F			; increase counter
-	bsf		message_warning				; YES - set warning flag
+	bsf		message_warning				; set warning flag
-	goto	TFT_warning_sensor_disagree	;       show sensor disagree warning (and return)
+	btfsc	o2_sensors_warning			; is it a new warning?
+	goto	TFT_warning_sensor_disagree	; NO  - don't show sensor custom view again, just show sensor disagree warning and return
+	bsf		o2_sensors_warning			; YES - memorize it's an old warning now
+	call	show_sensors_custview		;     - show sensors custom view
+	goto	TFT_warning_sensor_disagree	;     - show sensor disagree warning and return
+ENDIF
+;=============================================================================
+IFDEF _helium
 check_IBCD:
 	TSTOSS	opt_enable_IBCD				; IBCD warning activated?
 	return								; NO  - done
 	movff	char_O_deco_warnings,WREG	; YES - get deco warnings vector
 	btfss	WREG,IBCD_warning			;       IBCD warning flag set?
 	return								;       NO  - return
 	incf	message_counter,F			;       YES - increase counter
 	goto	TFT_warning_IBCD			;             write warning to display
+ENDIF
+;=============================================================================
 check_OC_gas_avail:
-	tstfsz	best_gas_number				; is a breathable gas available?
+	tstfsz	best_gas_number				; is a breathable OC (bailout) gas available?
-	return								; > 0 : a breathable gas is available
+	return								; YES (>0) - a breathable gas is available
-	btfsc	FLAG_ccr_mode				; = 0 : problem - in CCR mode?
+	btfsc	bailout_mode				; NO  (=0) - in bailout?
-	bra		check_OC_gas_avail_1		; YES - real problem
+	return								;            YES - suppress warning
-	btfsc	FLAG_pscr_mode				; NO  - in PSCR mode?
+	incf	message_counter,F			;            NO  - increase counter
-	bra		check_OC_gas_avail_1		;       YES - real problem
+	bsf		message_warning				;                - set attention flag
-	return								;       NO  - neither CCR nor pSCR mode, suppress warning
+	goto	TFT_warning_no_BO_gas		;                - show waring (and return)
-check_OC_gas_avail_1:
-	btfsc	FLAG_bailout_mode			; in bailout?
-	return								; YES - suppress warning
-	incf	message_counter,F			; NO  - increase counter
-	bsf		message_attention			;       set attention flag
-	goto	TFT_warning_no_BO_gas		;       show message (and return)
 advice_gas_change:
 	bsf		message_advice				; show advice sign
 	incf	message_counter,F			; increase counter
 	global	restart_deco_engine
 	global	restart_deco_engine_wo_ceiling
 restart_deco_engine:
-	; invalidate ceiling
+	banksel	int_O_ceiling								; switch to bank where the shared "_O_" variables are stored
-	movff	int_O_ceiling+1,WREG
+	bsf		int_O_ceiling+1,char_invalid_flag			; invalidate ceiling (int_O_ceiling has its invalid flag on a char's position!)
-	bsf		WREG,char_invalid_flag		; int_O_ceiling has its invalid flag on a char's position!
-	movff	WREG,int_O_ceiling+1
 restart_deco_engine_wo_ceiling:
-	; invalidate deco data (stop table data)
+	banksel	char_O_deco_gas								; switch to bank where the shared "_O_" variables are stored
-	movff	char_O_deco_gas+0,WREG
+	bsf		char_O_deco_gas+0,char_invalid_flag			; invalidate deco data (stop table data)
-	bsf		WREG,char_invalid_flag
+	bsf		int_O_TTS_norm+1,int_invalid_flag			; invalidate ascent time (normal plan)
-	movff	WREG,char_O_deco_gas+0
+	bsf		int_O_CNS_norm+1,int_invalid_flag			; invalidate CNS at end of dive in normal plan
+														; restart deco engine:
-	; invalidate ascent time (normal plan)
+	bcf		char_O_deco_status,DECO_COMPLETED_NORM		; eventually clear flag stating completion of normal plan
-	movff	int_O_ascenttime+1,WREG
+	bsf		char_O_deco_status,DECO_COMPLETED_ALT		; fake we came from alternative plan to force normal plan to be done next
-	bsf		WREG,int_invalid_flag
-	movff	WREG,int_O_ascenttime+1
-	; invalidate CNS at end of dive in normal plan
-	movff	int_O_normal_CNS_fraction+1,WREG
-	bsf		WREG,int_invalid_flag
-	movff	WREG,int_O_normal_CNS_fraction+1
-	; restart deco engine
-	movff	char_O_main_status,WREG		; get current main engine configuration
-	bcf		WREG,DECO_COMPLETED_NORM	; eventually clear flag stating completion of normal plan
-	bsf		WREG,DECO_COMPLETED_ALT		; fake we came from alternative plan to force normal plan to be done next
-	movff	WREG,char_O_main_status		; write back new configuration
-	movff	char_O_deco_status,WREG		; get current deco engine status
-	bcf		WREG,DECO_STATUS_0_FLAG		; set status flags to...
-	bcf		WREG,DECO_STATUS_1_FLAG		; ... DECO_STATUS_START
-	movff	WREG,char_O_deco_status		; write back new configuration to restart deco computations
 inval_alternative_plan_data:
-	; invalidate ascent time (alternative plan)
+	banksel	int_O_TTS_alt								; switch to bank where the shared "_O_" variables are stored
-	movff	int_O_alternate_ascenttime+1,WREG
+	bsf		int_O_TTS_alt+1,int_invalid_flag			; invalidate ascent time (alternative plan)
-	bsf		WREG,int_invalid_flag
+	bsf		int_O_CNS_alt+1,int_invalid_flag			; invalidate CNS at end of dive in alternative plan
-	movff	WREG,int_O_alternate_ascenttime+1
+	bsf		int_O_gas_need_pres+1,int_invalid_flag		; invalidate ascent gas needs
-	; invalidate CNS at end of dive in alternative plan
-	movff	int_O_alternate_CNS_fraction+1,WREG
-	bsf		WREG,int_invalid_flag
-	movff	WREG,int_O_alternate_CNS_fraction+1
-	; invalidate ascent gas needs
-	movff	int_O_ascent_pres_need+1,WREG
-	bsf		WREG,int_invalid_flag
-	movff	WREG,int_O_ascent_pres_need+1
 IFDEF _rx_functions
-	; invalidate pressure needs (TR functions)
+	bsf		int_O_pressure_need+1,int_not_avail_flag	; invalidate pressure needs to reading 1 (TR functions)
-	movff	int_O_pressure_need+1,WREG
+	bsf		int_O_pressure_need+3,int_not_avail_flag	; invalidate pressure needs to reading 2 (TR functions)
-	bsf		WREG,int_not_avail_flag
+ENDIF
-	movff	WREG,int_O_pressure_need+1
-	movff	int_O_pressure_need+3,WREG
+	banksel	common										; bank to bank common
-	bsf		WREG,int_not_avail_flag
+	bsf		new_deco_data_avail							; set flag for new NDL and deco data available to have the display updated
-	movff	WREG,int_O_pressure_need+3
-ENDIF
-	; update display depended on NDL or deco mode
-	bsf		FLAG_TFT_display_ndl_or_deko
 	return
 ;=============================================================================
 ; Simulator Mode
 ;
 	global	do_demo_divemode
 do_demo_divemode:
+	; +++ COMMENT OUT FOR TESTING PURPOSE ONLY  !!! +++
+	bsf		simulatormode					; will restore tissue pressures and CNS value after simulator use
+	; +++ DO NOT COMMENT OUT IN OPERATIONAL USE !!! +++
 	call	TFT_ClearScreen					; blank screen
 	call	option_save_all					; save all settings into EEPROM before starting simulation
-	call	deco_push_tissues_to_vault		; C-code: back-up status of the real tissues
+	call	deco_push_tissues_to_vault		; back-up the tissue pressures (C-code)
-	banksel	common							; bank 1
+	banksel	common							; back to bank common
-	; +++ COMMENT OUT FOR TESTING PURPOSE ONLY  !!! +++
+	; set simulated target depth
-	bsf		restore_deco_data				; restore tissue and CNS after simulator use
+	movff	char_I_bottom_depth,simulatormode_depth
-	; +++ DO NOT COMMENT OUT IN OPERATIONAL USE !!! +++
+	; set initial simulated depth (needed to overcome end-of-dive detection)
-	bcf		pressure_refresh
+	banksel	pressure_rel_sim
-	btfss	pressure_refresh				; wait for sensor
+	MOVLI	simulator_startdepth,pressure_rel_sim
-	bra		$-2
+	banksel	common
-	bsf		simulatormode_active			; set flag
+	; switch ISR pressure calculations to simulator mode
+	bcf		quit_simulatormode				; clear flag for fast abort request
-	banksel	char_I_bottom_depth				; compute dive ambient conditions
+	bcf		sensor_override_active			; make sure ISR mode switch confirmation is not older than from now on
-	movf	char_I_bottom_depth,W
+	bsf		sensor_override_request			; request ISR to switch to simulator mode
-	mullw	.100
+	btfss	sensor_override_active			; has the ISR confirmed switch to simulator mode?
-	movff	PRODL,rel_pressure+0
+	bra		$-2								; NO - not yet, loop waiting for the ISR to kick in
-	movff	PRODH,rel_pressure+1
-	movlw	LOW  (.1000)
+	; branch into dive mode
-	addwf	PRODL,W
+	bsf		divemode						; activate  dive mode (to be done after simulator mode is activated)
-	movff	WREG,sim_pressure+0
+	goto	diveloop						; branch to dive mode code
-	movlw	HIGH (.1000)
-	addwfc	PRODH,W
-	movff	WREG,sim_pressure+1
-	banksel	common							; bank 1
-	bsf		divemode
-	goto	diveloop						; switch into dive mode
 	END

Mercurial > public > hwos_code

comparison src/divemode.asm @ 623:c40025d8e750