view src/divemode.asm @ 572:0039f057b90f

Fix time of dive in internal logbook
author heinrichsweikamp
date Mon, 12 Feb 2018 16:24:58 +0100
parents 54346c651b6a
children b455b31ce022
line wrap: on
line source

;=============================================================================
;
;   File divemode.asm								REFACTORED VERSION V2.96a
;
;   Divemode
;
;   Copyright (c) 2011, JD Gascuel, HeinrichsWeikamp, all right reserved.
;=============================================================================
; HISTORY
;  2011-08-15 : [mH] moving from OSTC code

#include    "hwos.inc"					; Mandatory header
#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"

gui     CODE

	global	diveloop
diveloop:
    banksel common
    call    speed_normal
    call    diveloop_boot				; Boot tasks for all modes

    ; Startup Tasks for all modes
    call    TFT_boot                	; Initialize TFT (includes clear screen)
    bsf	    FLAG_TFT_divemode_mask		; Display mask
    movff   customview_divemode,menupos3; Reload last customview
    call    customview_mask         	; Redraw last custom view

    btfsc   FLAG_apnoe_mode
    bsf	    realdive					; Set Realdive flag in Apnoe mode

    btfsc   FLAG_apnoe_mode             ; Done for Apnoe or Gauge mode
    bra     diveloop_loop_start
    btfsc   FLAG_gauge_mode             ; Done for Apnoe or Gauge mode
    bra     diveloop_loop_start

    bsf	    FLAG_TFT_display_ndl_mask	; display "NDL"

	; +@5 init
    clrf    WREG                    	; WAIT marker: display "---"
    movff   WREG,char_I_sim_advance_time; bank safe clrf
    movff   WREG,int_O_alternate_ascenttime+0
	bsf		WREG,int_not_yet_computed
	bsf		WREG,int_invalid_flag
    movff   WREG,int_O_alternate_ascenttime+1

diveloop_loop_start:
    btfsc   FLAG_TFT_display_ndl_mask
    call    TFT_display_ndl_mask


diveloop_loop:							; The diveloop starts here
    btfss   quarter_second_update
    bra     diveloop_loop4a

    ; tasks any 1/4 second, any mode
    bcf     quarter_second_update		; clear flag
    
    movlw   .6
    cpfseq  menupos3                    ; in compass view?
    bra     diveloop_loop4a				; No, done.

    btfsc   alternative_divelayout		; In alternative layout mode?
    bra	    diveloop_loop4a				; Yes, done. No Compass.

; TFT Output routines	
    extern  TFT_dive_compass_heading
    call    TFT_dive_compass_heading    ; Yes, update compass heading value
    bsf	    FLAG_TFT_temp_divemode		; Redraw temperature (Is slighty affected from compass heading arrow)
; TFT Output routines	

diveloop_loop4a:
	btfss	onesecupdate					
	bra		diveloop_loop3
	
; tasks any new second...
    bcf     onesecupdate				; one seconds update, clear flag here in case it's set again in ISR before all tasks are done.

	;bsf	LEDg	; ### DEBUG - used to measure the time used by all deco code to see if there is enough margin each second ###	

	; display depth based on full seconds interval (nicer blinking)
    btfss   alternative_divelayout
    rcall   TFT_output4_normal
    btfsc   alternative_divelayout
    rcall   TFT_output4_alternative
	
	btfsc	FLAG_apnoe_mode				; Only in apnoe mode
	bra		diveloop_loop1b				; One Second Tasks in Apnoe mode
	
; tasks any new second - only for deco modes
	bsf		FLAG_TFT_divemins			; Display (new) divetime!
	btfsc	show_safety_stop			; Show the safety stop?
	bsf		FLAG_TFT_show_safety_stop	; Yes, show/delete if done.

	btfss	alternative_divelayout
	rcall	TFT_output1_normal
	btfsc	alternative_divelayout
	rcall	TFT_output1_alternative

	btfsc   FLAG_ccr_mode				; In CCR mode...
	call    check_dive_autosp			; ...check for Auto-SP
	
	call	calc_deko_divemode			; calculate decompression and set resulting display flags

	btfss	alternative_divelayout
	rcall	TFT_output2_normal
	btfsc	alternative_divelayout
	rcall	TFT_output2_alternative

	call	divemode_check_for_warnings	; Check for any warnings

	bra		diveloop_loop1x				; Common Tasks

	
; tasks any new second - only for apnoe mode
diveloop_loop1b:
	rcall	divemode_apnoe_tasks		; 1 sec. Apnoe tasks
	call	customview_second			; Do every-second tasks for the custom view area

	;bra	diveloop_loop1x				; Common Tasks

; continue tasks any new second, any mode
diveloop_loop1x:
	rcall	timeout_divemode			; ** menu timeout? ** This routine sets the required flags
	rcall	set_dive_modes				; tests if depth>threshold
	rcall	set_min_temp				; store min. temp if required (Future hardware will need this to be checked 1/second...)

	btfsc	oneminupdate				; one minute tasks
	rcall	update_divemode60			; Update clock, etc.

	btfss	alternative_divelayout
	rcall	TFT_output3_normal
	btfsc	alternative_divelayout
	rcall	TFT_output3_alternative

	;bcf	LEDg	; ### DEBUG - used to measure the time used by all deco code to see if there is enough margin each second ###

; tasks any round, any mode
diveloop_loop3:
    call	test_switches_divemode		; Check switches in divemode
	
    global  diveloop_loop4
diveloop_loop4:							; Menu-Exit returns here...
	btfsc	divemode_menu				; in the big divemode menu?
	bra		diveloop_loop4b				; YES - no space for CCR/pSCR info
	btfsc	menuview					; NO  - in the small yellow menu?
	bra		diveloop_loop4b				; 		YES - no space for CCR/pSCR info
	btfsc	alternative_divelayout		; 		NO  - in the alternative layout?
	bra		diveloop_loop4b				; 			  YES - no space for CCR/pSCR info
	call	TFT_show_mode_divemode		; 			  NO  - (re)write CCR/pSCR mode info to display
diveloop_loop4b:
    btfsc   toggle_customview			; Next view?
    call    customview_toggle			; Yes, show next customview (and delete this flag)

    btfsc   store_sample				; store new sample?
    call    store_dive_data				; Store profile data

    btfss   divemode					; Dive finished?
    goto    ghostwriter_end_dive    	; Dive finished!

    btfsc   divemode_gaschange			; Gas switch flag set?
    call    gas_switched_common			; Yes

    btfsc   toggle_gf					; =1: Toggle GF/aGF
    rcall   divemodemode_togglegf		; Toggle aGF/GF
    
    btfsc   pressure_refresh			; new pressure available?	
    rcall   set_max_depth				; update max. depth if required
    btfsc   pressure_refresh			; new pressure available?	
    bsf	    FLAG_TFT_depth				; Yes, update depth asap
    bcf	    pressure_refresh			; clear flag

    btfsc   temp_changed
    bsf	    FLAG_TFT_temp_divemode		; Displays temperature

	; display depth based on as-fast-as-possible (no nice blinking)
    ;btfss   alternative_divelayout
    ;rcall   TFT_output4_normal
    ;btfsc   alternative_divelayout
    ;rcall   TFT_output4_alternative
    
    btfsc   enable_screen_dumps			; =1: Ignore vin_usb, wait for "l" command (Screen dump)
    bra     diveloop_loop5
    bra     diveloop_loop6

diveloop_loop5:
    btfss   vusb_in						; USB (still) plugged in?
    bcf     enable_screen_dumps			; No, clear flag
    call    rs232_get_byte
    btfsc   rs232_recieve_overflow
    bra     diveloop_loop6
    movlw   "l"
    cpfseq	RCREG1
    bra     diveloop_loop6
    call    TFT_dump_screen				; Dump the screen contents
	
diveloop_loop6:
	bra		diveloop_loop				; Loop the divemode
	
;--------------------------------------------------------------------------------------------------------	
	
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) divetime!
	call	customview_second			; Do every-second tasks for the custom view area (In sync with the divetime) 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_divemins
	call	TFT_divemins_alternative	; Display (new) divetime!
	btfsc	FLAG_TFT_divemode_mask_alt
	call    TFT_divemode_mask_alternative	; Alt. mask
	call	customview_alternative_second	; Do every-second tasks for the custom view area (In sync with the divetime) mH
	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
	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_active_gas_divemode
	call	TFT_active_gas_divemode			; Display gas/Setpoint
	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, any mode
	btfsc	FLAG_TFT_max_depth_alt
	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...)
	btfsc	FLAG_TFT_big_deco_alt
	call	TFT_big_deco_alt			; Big deco
	return

TFT_output4_normal:						; tasks any round, any mode
	btfsc	FLAG_TFT_depth
	call	TFT_depth					; Displays new depth
	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					; Displays new depth
	return
	
	
;--------------------------------------------------------------------------------------------------------

divemode_apnoe_tasks:					; 1 sec. Apnoe tasks
	call	TFT_display_apnoe_descent	; Yes, Show descent timer
	call	TFT_max_depth				; use normal max. depth

	btfsc	divemode2					; Time running?
	bra		divemode_apnoe_tasks2		; New descent, reset data if flag is set

	rcall	apnoe_calc_maxdepth
	call	TFT_display_apnoe_surface
	call	TFT_display_apnoe_last_max	; Show last max. depth
	incf	apnoe_surface_secs,F
	movlw	d'60'
	cpfseq	apnoe_surface_secs
	bra		divemode_apnoe_tasks1
	clrf	apnoe_surface_secs
	incf	apnoe_surface_mins,F

divemode_apnoe_tasks1:	
	bcf	FLAG_active_descent				; Clear flag
	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
	movff	apnoe_max_pressure+1,sub_a+1
	movff	max_pressure+0,sub_b+0
	movff	max_pressure+1,sub_b+1
	call	subU16						; sub_c = sub_a - sub_b
										; apnoe_max_pressure<max_pressure -> neg_flag=1
										; max_pressure<=apnoe_max_pressure -> neg_flag=0
	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_deko_divemode:
	rcall	calc_deko_divemode2			; all deco relevant code is now invoked every second
	btfsc	twosecupdate
	bra		calc_deko_divemode1
	bsf		twosecupdate
	return
	
calc_deko_divemode1:					; the following code is invoked every 2 seconds
	bcf		twosecupdate
	
	call	calc_average_depth			; calculate average depth
	call	calc_velocity				; calculate vertical velocity and display if > threshold (every two seconds)
	call	set_reset_safety_stop		; Set flags for safety stop and/or reset safety stop
	call	TFT_debug_output

	btfsc	FLAG_apnoe_mode				; Done for Apnoe or Gauge mode
	return
	btfsc	FLAG_gauge_mode				; Done for Apnoe or Gauge mode
	return

; Check for a gas change
	goto	check_gas_change			; Checks if a better gas should be selected (by user) and return...

	
calc_deko_divemode2:
	btfsc	FLAG_gauge_mode				; Done for Apnoe or Gauge mode
	return

	btfsc	FLAG_ccr_mode				; In CCR mode?
	rcall	calc_deko_divemode_sensor	; do sensor data acquisition if applicable by OSTC model

    btfsc   FLAG_pscr_mode				; In PSCR mode?
    rcall   calc_deko_divemode_sensor	; do sensor data acquisition if applicable by OSTC model
    
	SAFE_2BYTE_COPY amb_pressure,int_I_pres_respiration ; transfer ambient pressure to deco engine


	; 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
	;         the alternative plan last.
	
	; check state of ascent/deco calculations
	movff	char_O_deco_status,lo		; get a working copy of char_O_deco_status into bank common
	movlw	DECO_STATUS_MASK			; load bit mask covering the deco status bits
	andwf	lo,W						; mask out bits showing deco engine computations state
	tstfsz	WREG						; check if the last compute cycle has finished (bits 1 and 0 cleared)
	bra		calc_deko_divemode2e		; NO  - computations still in progress, needs more computation cycles
	btfss	lo,DECO_PLAN_FLAG			; YES - computation cycle finished, so check what has been computed
	bra		calc_deko_divemode2b		; PLAN bit is cleared i.e. normal plan was done, may do alternative next

	; The PLAN bit is set, i.e. an alternative plan was computed in the last cycle, or the deco engine has
	; been restarted because of a gas change etc. --> Reconfigure to normal plan for next computation cycle.
	
	; reset flags for special calculations
	bcf		lo,DECO_PLAN_FLAG			; clear flag for alternative plan
	bcf		lo,DECO_ASCENT_FLAG			; clear flag for delayed ascent calculation
	bcf		lo,DECO_VOLUME_FLAG			; clear flag for gas needs calculation
	movff	lo,char_O_deco_status		; write-back char_O_deco_status to deco engine interface

	; check if a switchback from CCR or pSCR bailout calculation is to be done
	btfsc	FLAG_ccr_mode				; may a switchback from a CCR bailout calculation be needed?
	bra		calc_deko_divemode2a		; in CCR  mode, so may need to switch back from bailout calculation
	btfsc	FLAG_pscr_mode				; may a switchback from a pSCR bailout calculation be needed?
	bra		calc_deko_divemode2a		; in pSCR mode, so may need to switch back from bailout calculation
	bra		calc_deko_divemode2e		; not in CCR nor pSCR, so no switchback needed, start normal plan now
										; (first cycle omits gas needs calculation in OC without delayed ascent)

	; switch back to loop calculation if last cycle was doing a bailout calculation
calc_deko_divemode2a:					
	movff	opt_calc_asc_gasvolume,hi	; get the gas volume needs calculation setting
	movf	hi,W						; are gas volume calculations turned on?
	bz		calc_deko_divemode2e		; NO  - can't have done a bailout calculation then, start normal plan
	btfsc	is_bailout					; YES - check if a real bailout situation is present
	bra		calc_deko_divemode2e		; YES - OC gases have been set by bailout action then, start normal plan
	movff	active_gas,WREG				; NO  - switch back to loop calculation: get current (diluent) gas, ...
	call	deco_setup_cc_diluents		;       ... set up deco calculations in CCR/pSCR mode with diluents,
	bra		calc_deko_divemode2e		;       ... and start in normal plan mode

	; The PLAN bit was cleared, i.e. a normal plan was computed in the last cycle. For the next
	; computation cycle the mode may be switched to alternative plan, or stay in normal mode...
	
calc_deko_divemode2b:
	bcf		lo,DECO_ASCENT_FLAG			; clear flag for delayed ascent calculation (for safety only)
	btfsc	is_bailout					; check if a real bailout situation is present
	bra		calc_deko_divemode2c		; YES - stay in normal plan mode and preclude delayed ascent calculation
	movff	char_I_extra_time,hi		; NO  -	get the delayed ascent setting
	tstfsz	hi							; 		check if delayed ascent calculation is enabled
	bsf		lo,DECO_ASCENT_FLAG			; 		YES - set flag for delayed ascent calculation
	tstfsz	hi							; 		check if delayed ascent calculation is enabled (again)
	bsf		lo,DECO_PLAN_FLAG			; 		YES - set flag for alternative plan

	; check if a gas needs calculation shall be done
calc_deko_divemode2c:					
	bsf		lo,DECO_VOLUME_FLAG			; set gas needs calculation flag (may be cleared again next)
	TSTOSS  opt_calc_asc_gasvolume		; check if gas needs calculation is enabled
	bcf		lo,DECO_VOLUME_FLAG			; NO  - reset flag again
	movff	lo,char_O_deco_status		; write-back char_O_deco_status to deco engine interface
	TSTOSS  opt_calc_asc_gasvolume		; check if gas volume calculation is enabled (again)
	bra		calc_deko_divemode2e		; NO  - no volume calculation, no simulated bailout plan in no case
	
	; check if conditions are met to calculate a bailout plan
	btfsc	is_bailout					; check if a real bailout situation is present
	bra		calc_deko_divemode2e		; YES - normal plan already does bailout (OC) calculation "for real"
	btfss	lo,DECO_MODE_LOOP_FLAG		; NO  - have loop mode calculation been done during the normal plan?
	bra		calc_deko_divemode2e		; NO  - when not in loop mode, no simulated bailout to be done
	bsf		lo,DECO_PLAN_FLAG			; YES - set flag for alternative plan
	movff	lo,char_O_deco_status		; 		write-back char_O_deco_status to deco engine interface
	call    get_first_gas_to_WREG		; 		get first OC gas, ...
	call	deco_setup_oc_gases			;       ... set up deco calculations in OC mode with OC gases,
	;bra	calc_deko_divemode2e		;       ... and start in alternative plan mode


calc_deko_divemode2e:
    clrf    TMR5L
    clrf    TMR5H                       ; 30,51757813µs/bit in TMR5L:TMR5H
	call	deco_calc_hauptroutine		; calc_tissue
	banksel common

    ; Check if deco stops are necessary ?
	movff	char_O_first_deco_depth,wait_temp	; copy ceiling to temp register
	tstfsz	wait_temp							; Ceiling<0m?
	bra		calc_deko_divemode3					; Yes!

	btfsc	decostop_active             		; Already in nodeco mode ?
	bsf		FLAG_TFT_display_ndl_mask       	; No, Clear deco data, display nostop time
	bcf		decostop_active						; clear flag (again)

	; Copy for profile recording
	clrf	decodata+0
	movff	char_O_nullzeit,decodata+1 			; NDL
	
	bsf		FLAG_TFT_display_ndl				; display no deco limit
	return

calc_deko_divemode3:
	btfss	decostop_active						; Already in deco mode ?
	bsf		FLAG_TFT_display_deko_mask			; No, clear nostop time, display decodata
	bsf		decostop_active						; Set flag (again)

	; Copy for profile recording
	movff	char_O_first_deco_depth,decodata+0	; ceiling
	movff	char_O_first_deco_time,decodata+1	; length of first stop in minutes
	bsf		FLAG_TFT_display_deko				; display decodata
	bsf		FLAG_TFT_display_tts				; display TTS
	return

	; --------------------------------------------------------------------------------------

	global	calc_deko_divemode_sensor
calc_deko_divemode_sensor:
	; sensor acquisition code
	btfss   s8_digital				; check if we have digital interface to the sensors
	bra     calc_deko_divemode_sensor_analog	; NO  - use analog interface
	btfss   new_s8_data_available			; YES - check if a new data frame was received
	bra	calc_deko_divemode_sensor_common	; NO  - use old values
	call	compute_mvolts_for_all_sensors		; YES - compute mV values from digital data
	bra	calc_deko_divemode_sensor_common

calc_deko_divemode_sensor_analog:
	call    get_analog_inputs					; TODO: abort when OSTC model does not have analog inputs

calc_deko_divemode_sensor_common:
	; Check for each sensor if it is calibrated and if its mv value is within min_mv and max_mv limits.
	; If     ok: compute o2_ppo2_sensorX := o2_mv_sensorX * opt_x_sX / 1000.
	; If not ok: reset o2_ppo2_sensorX, reset use_O2_sensorX and show the customview 1 in case the sensor was ok before.

	; Check min_mv of sensor 1
	btfss	sensor1_calibrated_ok			; check if sensor is usable at all
	bra		check_sensor_1_fail				; NO  - handle it as failed
	movff	o2_mv_sensor1+0, sub_a+0		; load sensor mV value
	movff	o2_mv_sensor1+1, sub_a+1
	movlw	LOW		min_mv					; load minimum mV value
	movwf	sub_b+0
	movlw	HIGH	min_mv
	movwf	sub_b+1
	call	sub16							; sub_c = sensor_mv - min_mv
    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_mv of sensor 1				  NO  - continue with next check
	movff	o2_mv_sensor1+0, sub_a+0
	movff	o2_mv_sensor1+1, sub_a+1
	movlw	LOW		max_mv
	movwf	sub_b+0
	movlw	HIGH	max_mv
	movwf	sub_b+1
	call	sub16							;  sub_c = sensor_mv - max_mv
	btfss	neg_flag						; check if result is negative, i.e. sensor_mv < max_mv
	bra		check_sensor_1_fail				; NO  - declare sensor as failed
	; Check HUD data, if available			  YES - continue with next check
	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 - check HUD report on sensor
	bra		check_sensor_1_fail				; HUD reports a fail

check_sensor_1_ok:
	; o2_ppo2_sensor1 := o2_mv_sensor1:2 * opt_x_s1:2 / 1000
	movff	o2_mv_sensor1+0,xA+0
	movff	o2_mv_sensor1+1,xA+1
	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 0.01bar
	bra	check_sensor_2						; continue with next sensor

check_sensor_1_fail:
	clrf	WREG
	movff	WREG,o2_ppo2_sensor1			; 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
check_sensor_1_fail_1:
	bcf		use_O2_sensor1					; revoke sensor from usage
	;bra	check_sensor_2					; continue with next sensor

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
	movff	o2_mv_sensor2+0, sub_a+0		; load sensor mV value
	movff	o2_mv_sensor2+1, sub_a+1
	movlw	LOW		min_mv					; load minimum mV value
	movwf	sub_b+0
	movlw	HIGH	min_mv
	movwf	sub_b+1
	call	sub16							; sub_c = sensor_mv - min_mv
    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_mv of sensor 2				  NO  - continue with next check
	movff	o2_mv_sensor2+0, sub_a+0
	movff	o2_mv_sensor2+1, sub_a+1
	movlw	LOW		max_mv
	movwf	sub_b+0
	movlw	HIGH	max_mv
	movwf	sub_b+1
	call	sub16							;  sub_c = sensor_mv - max_mv
	btfss	neg_flag						; check if result is nagative, i.e. sensor_mv < max_mv
	bra		check_sensor_2_fail				; NO  - declare sensor as failed
	; Check HUD data, if available			  YES - continue with next check
	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 - check HUD report on sensor
	bra		check_sensor_2_fail				; HUD reports a fail

check_sensor_2_ok:
	; o2_ppo2_sensor2 := o2_mv_sensor2:2 * opt_x_s2:2 / 1000
	movff	o2_mv_sensor2+0,xA+0
	movff	o2_mv_sensor2+1,xA+1
	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 0.01bar
	bra	check_sensor_3						; continue with next sensor

check_sensor_2_fail:
	clrf	WREG
	movff	WREG,o2_ppo2_sensor2			; 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
check_sensor_2_fail_1:
	bcf		use_O2_sensor2					; revoke sensor from usage
	;bra	check_sensor_3					; continue with next sensor	

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
	movff	o2_mv_sensor3+0, sub_a+0		; load sensor mV value
	movff	o2_mv_sensor3+1, sub_a+1
	movlw	LOW		min_mv					; load minimum mV value
	movwf	sub_b+0
	movlw	HIGH	min_mv
	movwf	sub_b+1
	call	sub16							; sub_c = sensor_mv - min_mv
    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_mv of sensor 2				  NO  - continue with next check
	movff	o2_mv_sensor3+0, sub_a+0
	movff	o2_mv_sensor3+1, sub_a+1
	movlw	LOW		max_mv
	movwf	sub_b+0
	movlw	HIGH	max_mv
	movwf	sub_b+1
	call	sub16							;  sub_c = sensor_mv - max_mv
	btfss	neg_flag						; check if result is nagative, i.e. sensor_mv < max_mv
	bra		check_sensor_3_fail				; NO  - declare sensor as failed
	; Check HUD data, if available			  YES - continue with next check
	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 - check HUD report on sensor
	bra		check_sensor_3_fail				; HUD reports a fail

check_sensor_3_ok:
	; o2_ppo2_sensor3 := o2_mv_sensor3:2 * opt_x_s1:2 / 1000
	movff	o2_mv_sensor3+0,xA+0
	movff	o2_mv_sensor3+1,xA+1
	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 0.01bar
	bra		calc_deko_divemode_sensor1		; continue with calculating sensor average

check_sensor_3_fail:
	clrf	WREG
	movff	WREG,o2_ppo2_sensor3			; 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 customview 1 (sensor values) on further conditions met
check_sensor_3_fail_1:
	bcf		use_O2_sensor3					; revoke sensor from usage
	;bra	calc_deko_divemode_sensor1		; continue with calculating sensor average
	
calc_deko_divemode_sensor1:					; calculate sensor average
	; exit here if not in divemode
	btfss	divemode
	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
    clrf    xB+1
    clrf    xA+0
    clrf    xA+1
    btfss   use_O2_sensor1                  ; Sensor1 active?
    bra     divemode_setup_sensor_values2   ; No
    movf    o2_ppo2_sensor1,W
    addwf   xA+0
    movlw   .0
    addwfc  xA+1                            ; Add into xA:2
    incf    xB+0,F                          ; Add a sensor
divemode_setup_sensor_values2:
    btfss   use_O2_sensor2                  ; Sensor2 active?
    bra     divemode_setup_sensor_values3   ; No
    movf    o2_ppo2_sensor2,W
    addwf   xA+0
    movlw   .0
    addwfc  xA+1                            ; Add into xA:2
    incf    xB+0,F                          ; Add a sensor
divemode_setup_sensor_values3:
    btfss   use_O2_sensor3                  ; Sensor3 active?
    bra     divemode_setup_sensor_values4   ; No
    movf    o2_ppo2_sensor3,W
    addwf   xA+0
    movlw   .0
    addwfc  xA+1                            ; Add into xA:2
    incf    xB+0,F                          ; Add a sensor

	; Divide sum of sensor values by number of active sensors found.
divemode_setup_sensor_values4:
    call    div16x16						; xA/xB=xC with xA+0 as remainder
    movff   xC+0,sensor_setpoint            ; copy result
	
	; 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
	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	is_bailout						; check if we are in bailout
	bra		calc_deko_divemode_sensor2		; YES - no sensor data transfer to char_I_const_ppO2 in this case
	movff   opt_ccr_mode,WREG               ; =0: Fixed SP, =1: Sensor,  =2: Auto SP
    sublw   .1                              ; opt_ccr_mode = 1 (Sensor)?
    bnz     calc_deko_divemode_sensor2		; not in sensor mode - no transfer of sensor data to char_I_const_ppO2
	tstfsz	xB+0							; check if we have found at least one usable sensor
	bra		calc_deko_divemode_sensor1a		; YES - we have at least one usable sensor
	bsf		setpoint_fallback				; NO  - we have NO usable sensors -> initiate fallback
	btfss	FLAG_ccr_mode					; check if we are in CCR mode
	bra		calc_deko_divemode_sensor2		; NO  - continue with voting logic flags
	movff	char_I_setpoint_cbar+0,char_I_const_ppO2	; YES - select fixed setpoint no. 1 for fallback
	bra		calc_deko_divemode_sensor2		; done - continue with voting logic flags
calc_deko_divemode_sensor1a:				; we have at least one usable sensor with a value > 0
	bcf		setpoint_fallback				; clear fallback condition
	movff	sensor_setpoint,char_I_const_ppO2	; transfer average sensor value to p2_deco.c code
	; bra	calc_deko_divemode_sensor2

calc_deko_divemode_sensor2:
    bsf     voting_logic_sensor1
    movff   o2_ppo2_sensor1,temp1
    rcall   check_sensor_voting_helper
    incfsz  WREG                    		; Was Wreg=255?
    bcf     voting_logic_sensor1    		; No, ignore this sensor

    bsf     voting_logic_sensor2
    movff   o2_ppo2_sensor2,temp1
    rcall   check_sensor_voting_helper
    incfsz  WREG                    		; Was Wreg=255?
    bcf     voting_logic_sensor2    		; No, ignore this sensor

    bsf     voting_logic_sensor3
    movff   o2_ppo2_sensor3,temp1
    rcall   check_sensor_voting_helper
    incfsz  WREG                    		; Was Wreg=255?
    bcf     voting_logic_sensor3    		; No, ignore this sensor
	
	; check if a warning shall be issued on sensor disagreement

	btfsc	FLAG_ccr_mode					; check if we are in CCR mode
	bra 	check_warn_sensor_1				; YES - continue with further checks
	btfsc	FLAG_pscr_mode					; check if we are in pSCR mode
	bra		check_warn_sensor_1				; YES - continue with further checks
	bra 	check_warn_sensor_agree			; not in CCR and not in pSCR, so no warning
check_warn_sensor_1:						; we are in CCR or pSCR mode
	btfsc	is_bailout						; check if we are in bailout
	bra		check_warn_sensor_agree			; YES - no warning in this case
	movff   opt_ccr_mode,WREG               ; =0: Fixed SP, =1: Sensor,  =2: Auto SP
    sublw   .1                              ; opt_ccr_mode = 1 (Sensor)?
    bnz     check_warn_sensor_agree			; not in sensor mode - no warning in this case
											; check sensor 1
	btfss	sensor1_calibrated_ok			; check if sensor has a valid calibration
	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
	return

check_warn_sensor_2:						; check 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
	return
	
check_warn_sensor_3:						; check sensor 2
	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
	return
					
check_warn_sensor_agree:
	bsf		sensors_agree
	return

compute_ppo2_helper:
	call	mult16x16						;xA:2*xB:2=xC:4
	movlw	LOW		.1000
	movwf	xB+0
	movlw	HIGH	.1000
	movwf	xB+1
	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 interessed in the carry flag
	movlw	d'0'
	addwfc	xC+1,W							; we are still just interessed 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 divemode
	return									; NO  - not in dive mode, return
    movff   opt_ccr_mode,WREG               ; =0: Fixed SP, =1: Sensor,  =2: Auto SP
    sublw   .1                              ; opt_ccr_mode = 1 (Sensors)?
    bnz		check_sensor_helper_1			; NO  - not using the sensors in the moment
	clrf	menupos3						; YES - arm customview 1 (sensor values)
	bsf		toggle_customview				;       and request a customview toggle
check_sensor_helper_1:
	return

	
check_sensor_voting_helper:
    movf    temp1,W
    cpfsgt  sensor_setpoint
    bra     check_sensor_voting_common2		; temp1<sensor_setpoint
    ; temp1>sensor_setpoint
    movf    temp1,W
    subwf   sensor_setpoint,W
    movwf   temp1
check_sensor_voting_common1:
    movlw	sensor_voting_logic_threshold	; Threshold in 0.01 bar
    cpfsgt  temp1
    retlw   .255							; Within range
    retlw   .0								; Out of range
check_sensor_voting_common2:
    ; temp1<sensor_setpoint
    movf    sensor_setpoint,W
    subwf   temp1,F
    bra     check_sensor_voting_common1
		
;-----------------------------------------------------------------------------

divemodemode_togglegf:						; Toggle aGF/GF
    bcf     toggle_gf						; clear flag    
    btg     use_agf							; toggle GF

	movff	opt_GF_low,char_I_GF_Low_percentage
	movff	opt_GF_high,char_I_GF_High_percentage

	; Overwrite GF if aGF is wanted
	btfsc	use_agf							; =1: Use aGF
	movff	opt_aGF_low,char_I_GF_Low_percentage
	btfsc	use_agf							; =1: Use aGF
	movff	opt_aGF_high,char_I_GF_High_percentage

    call    TFT_gf_mask						; Setup Mask
	goto	restart_deco_engine				; ...and return


calc_velocity:								; called every two seconds
    btfsc   display_velocity                
    bra     calc_velocity1                  ; Always update if already displayed
	btfss	divemode2						
	return                      			; display velocity only if deepter 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'
	movwf	divB+0
	call	div16							; devided by 2^7 equals velocity in m/min

	movlw	d'99'
	cpfsgt	divA+0                      	; limit to 99m/min
	bra		calc_velocity3
	movwf	divA+0							; 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
    TSTOSS  opt_enable_safetystop           ; =1: A safety stop is shown
    bra		delete_safety_stop              ; No, don't show safety stop

	btfsc	decostop_active					; Is a deco stop displayed?
	bra		delete_safety_stop				; Yes, don't show safety stop

	; Below "opt_safety_stop_reset"? Set flag and reset count-down timer
    SAFE_2BYTE_COPY rel_pressure, lo
	call	adjust_depth_with_salinity		; computes salinity setting into lo:hi [mbar]
	movff	lo,sub_a+0
	movff	hi,sub_a+1
    movff   opt_safety_stop_reset,WREG      ; [cbar]
    mullw   .10                             ; mbar in PRODL:H
    movff   PRODL,sub_b+0
    movff   PRODH,sub_b+1
	call	subU16							; sub_c = sub_a - sub_b
	btfss	neg_flag
	bra		reset_safety_stop				; Below 10m, reset safety stop

	; Above "opt_safety_stop_end"? Clear flag.
    SAFE_2BYTE_COPY rel_pressure, lo
	call	adjust_depth_with_salinity		; computes salinity setting into lo:hi [mbar]
	movff	lo,sub_a+0
	movff	hi,sub_a+1
    movff   opt_safety_stop_end,WREG      	; [cbar]
    mullw   .10                             ; mbar in PRODL:H
    movff   PRODL,sub_b+0
    movff   PRODH,sub_b+1
	call	subU16							; sub_c = sub_a - sub_b
	btfsc	neg_flag
	bra		delete_safety_stop				; Above 3m, remove safety stop

	; Above "opt_safety_stop_start"? Activate safety stop
    SAFE_2BYTE_COPY rel_pressure, lo
	call	adjust_depth_with_salinity		; computes salinity setting into lo:hi [mbar]
	movff	lo,sub_a+0
	movff	hi,sub_a+1
    movff   opt_safety_stop_start,WREG      ; [cbar]
    mullw   .10                             ; mbar in PRODL:H
    movff   PRODL,sub_b+0
    movff   PRODH,sub_b+1
	call	subU16							;  sub_c = sub_a - sub_b
	btfsc	neg_flag
	bra		acivate_safety_stop				; Above 5m, activate safety stop
	bra		reset_safety_stop2				; Pause safety stop

acivate_safety_stop:
	tstfsz	safety_stop_countdown			; Countdown at zero?
	bsf		show_safety_stop				; No, Set flag!
	return

delete_safety_stop:
	clrf	safety_stop_countdown			; reset timer
	bra		reset_safety_stop2				; Remove safety stop from display

reset_safety_stop:
    movff   opt_safety_stop_length,safety_stop_countdown	; reset timer
reset_safety_stop2:
	bcf		show_safety_stop				; Clear flag
	btfss	safety_stop_active				; Safety stop shown
	return									; No, don't delete it
	bcf		safety_stop_active				; Clear flag
    bsf	    FLAG_TFT_clear_safety_stop		; Clear safety stop
    return


;=============================================================================

timeout_menuview:
    decfsz  timeout_counter3,F          ; timeout for menuview
    return                              ; No timeout, return
    ; Timeout, clear e.g. "Menu?"
    goto    menuview_toggle_reset       ; "returns"

timeout_divemode_menu:
    decfsz  timeout_counter3,F          ; timeout for divemode menu
    return

    global  timeout_divemode_menu2
timeout_divemode_menu2:                 ; Called from divemenu_tree.asm
    bcf     divemode_menu               ; Timeout! Clear flag
    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
    bsf	    FLAG_TFT_temp_divemode		; Displays temperature
    call    TFT_draw_gassep_line        ; Gas separator grid in spec mode only

    btfss   decostop_active             ; In deco mode ?
    bra     timeout_divemode_menu_ndl   ; No, show NDL again
    ; Show deco
    bsf	    FLAG_TFT_display_deko_mask
    bsf	    FLAG_TFT_display_deko
    bsf	    FLAG_TFT_display_tts
    return
    
timeout_divemode_menu_ndl:              
    ; Show NDL
    bsf	    FLAG_TFT_display_ndl_mask
    bsf	    FLAG_TFT_display_ndl
    return

timeout_divemode:
    btfsc   divemode_menu               ; Divemode menu active?
    rcall   timeout_divemode_menu       ; Yes, check the timeout for it...

    btfsc   menuview                    ; is a menuview shown?
    rcall   timeout_menuview            ; Yes, check the timeout for it...

	btfss	realdive					; Dive longer then one minute
	return
	
	btfsc	FLAG_apnoe_mode				; In Apnoe mode?
	bra		timeout_divemode2			; Yes, use apnoe_timeout [min] for timeout

    ifndef __DEBUG
    	btfsc	simulatormode_active    ; In Simulator mode?
    	bra		timeout_divemode3       ; Yes, use simulator timeout
    endif
	
	bcf		divemode
	infsnz  timeout_counter,F
    incf    timeout_counter2,F			; timeout is 15bits

	movff	opt_diveTimeout,WREG	    ; in [min]
	mullw	.60
	movff	PRODL,sub_a+0
	movff	PRODH,sub_a+1		    	; in [s]

	movff	timeout_counter, sub_b+0
	movff	timeout_counter2, sub_b+1
	call	subU16						;  sub_c = sub_a - sub_b
	btfss	neg_flag					; Result negative?
	bsf		divemode					; No, set flag
	return

timeout_divemode2:
	incf	timeout_counter,F			; seconds...
	movlw	d'60'
	cpfseq	timeout_counter				; timeout_counter=60?
	return								; No.
; One minute timeout done.
	clrf	timeout_counter
	bcf		divemode
	incf	apnoe_timeout_counter,F
	movlw	apnoe_timeout				; apnoe timeout [min]
	cpfseq	apnoe_timeout_counter
	bsf		divemode
	return

timeout_divemode3:
	bcf		divemode
	incf	timeout_counter,F
	movlw	simulator_timeout   		; simulator timeout
	cpfsgt	timeout_counter
	bsf		divemode
	return

update_divemode60:                      ; update any minute
	call	get_battery_voltage			; gets battery voltage
	rcall	set_powersafe				; Battery low?
	call	customview_minute			; Do every-minute tasks for the custom view area
	bcf	oneminupdate

    btfss   simulatormode_active        ; in simulator mode?
	return                              ; No
	; Yes, quite dive mode simulation after 21*256s=89min:36s
	movlw	.20
	cpfsgt	total_divetime_seconds+1	; Timeout?
	return                              ; No
    ifdef __DEBUG
    return                              ; No simulator timeout in debug mode
    endif
	bra		divemode_option1            ; Yes, set to 0m and "return"

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?
	bra		set_dive_modes3				; Yes!

set_dive_modes0:
	movlw	LOW		start_dive_threshold
	movwf	sub_a+0						; dive_treshold is in cm
	movlw	HIGH	start_dive_threshold
	movwf	sub_a+1						; dive_treshold is in cm

set_dive_modes1:
    SAFE_2BYTE_COPY rel_pressure, sub_b
	call	subU16						; sub_c = sub_a - sub_b

	btfss	neg_flag	
	bra		set_dive_modes2				; too shallow (rel_pressure<dive_threshold)

	btfsc	realdive					; Dive longer than one minute?
	clrf 	timeout_counter				; Yes, reset timout counter

	bsf		divemode					; (Re-)Set divemode flag
	bsf		divemode2					; displayed divetime is running
	return

set_dive_modes2:
	bcf		divemode2					; Stop time
	btfss	realdive					; dive longer then one minute?
	bcf		divemode					; no -> this was no real dive
	return								; No, return


set_dive_modes3:						; High-altitude mode
	btfsc	realdive					; dive longer then one minute?
	bra		set_dive_modes0				; Yes -> this is a real dive -> Use start_dive_threshold or ascend

	movlw	HIGH	high_altitude_dive_threshold
	movwf	sub_a+1
	movlw	LOW		high_altitude_dive_threshold
	movwf	sub_a+0
	bra		set_dive_modes1

set_powersafe:
    movlw   color_code_battery_low+1; [%]
    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
	return								; return

calc_average_depth:
	btfsc	reset_average_depth			; Reset the Average depth?
	rcall	reset_average1				; Reset the resettable average depth

	; 1. Add new 2xdepth to the Sum of depths registers
    SAFE_2BYTE_COPY rel_pressure, xB	; Buffer...
    bcf     STATUS,C
    rlcf    xB+0,F
    rlcf    xB+1,F                  	; x2

	movf	xB+0,w
	addwf	average_depth_hold+0,F
	movf	xB+1,w
	addwfc	average_depth_hold+1,F
	movlw	d'0'
	addwfc	average_depth_hold+2,F
	addwfc	average_depth_hold+3,F 		; Will work up to 9999mbar*60*60*24=863913600mbar

	; Do the same for the _total registers (Non-Resettable)
	movf	xB+0,w
	addwf	average_depth_hold_total+0,F
	movf	xB+1,w
	addwfc	average_depth_hold_total+1,F
	movlw	d'0'
	addwfc	average_depth_hold_total+2,F
	addwfc	average_depth_hold_total+3,F ; Will work up to 9999mbar*60*60*24=863913600mbar

	; 2. Compute Average Depth on base of average_divesecs:2
	movff	average_divesecs+0,xB+0
	movff	average_divesecs+1,xB+1		; Copy
	movff	average_depth_hold+0,xC+0
	movff	average_depth_hold+1,xC+1
	movff	average_depth_hold+2,xC+2
	movff	average_depth_hold+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+0
	movff	xC+1,avg_rel_pressure+1

    btfss   divemode2                   ; displayed divetime is running?
	return                              ; No (e.g. too shallow)

	; 3. Compute Total Average Depth on base of total_divetime_seconds:2
	movff	total_divetime_seconds+0,xB+0
	movff	total_divetime_seconds+1,xB+1		; Copy
	movff	average_depth_hold_total+0,xC+0
	movff	average_depth_hold_total+1,xC+1
	movff	average_depth_hold_total+2,xC+2
	movff	average_depth_hold_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
	movff	xC+1,avg_rel_pressure_total+1
	return

reset_average1:
	clrf	average_depth_hold+0
	clrf	average_depth_hold+1
	clrf	average_depth_hold+2
	clrf	average_depth_hold+3		; Clear average depth register
	movlw	d'2'
	movwf	average_divesecs+0
	clrf	average_divesecs+1
	bcf		reset_average_depth			; Clear flag
	return

test_switches_divemode:					; checks switches in divemode
    btfsc   divemode_menu               ; Divemode menu shown?
    bra     test_switches_divemode_menu ; Yes, use menu processor
	btfsc	switch_left
	; bra	test_switches_divemode2		; Enter button pressed, check if we need to do something
	goto    menuview_toggle         	; Menu or Simulator tasks; and return...
	btfss	switch_right
	return                              ; No button press
    tstfsz  menupos2                    ; any option shown?
    bra     test_switches_divemode1     ; Yes, do option tasks
	bsf		toggle_customview           ; No, toggle custom view
    return

test_switches_divemode_menu:
	btfsc	switch_left
	bra		test_switches_divemode_menu2    ; Move cursor
	btfsc	switch_right
    bra		test_switches_divemode_menu3    ; Enter submenu or do something
    return                                  ; No button press

test_switches_divemode_menu1:
    clrf    menupos
test_switches_divemode_menu2:
    incf    menupos,F
    incf    menupos4,W                  ; menupos4+1 -> WREG
    cpfslt  menupos                     ; >menupos4 (Set in menu_processor.asm)?
    bra     test_switches_divemode_menu1; > Yes, set to 1
    call    TFT_divemode_menu_cursor    ; Update the cursor
    bcf     switch_left
	movlw	divemode_menu_timeout       ; Reload timeout
	movwf	timeout_counter3            ; timeout for divemode menu
    return

test_switches_divemode_menu3:           ; Enter submenu or do something
    bcf     switch_right
;    decf    menupos,F					; menu_processor needs 0-5...
    extern  do_line_menu
    goto    do_line_menu                ; Warning! Trashes STKPTR and returns to diveloop_loop4:

test_switches_divemode1:
	bcf		switch_right
    movlw   divemode_menuview_timeout
    movwf   timeout_counter3            ; Reload timeout
	movff	menupos2,WREG               ; menupos2 holds number of customview/divemode menu function
	dcfsnz	WREG,F
    bra		divemode_option_gaschange	; Switch to the indicated "better gas"
	dcfsnz	WREG,F
    bra		divemode_option0			; Start/Setup Divemode 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
	dcfsnz	WREG,F
	bra		divemode_option4			; Quit Apnoe mode
	dcfsnz	WREG,F
	bra		divemode_option5			; Reset Stopwatch (In Gauge mode)
	dcfsnz	WREG,F
	bra		divemode_option6			; +5mins simulation
	dcfsnz	WREG,F
	bra		divemode_option7			; Store heading
	dcfsnz	WREG,F
	bra		divemode_option8			; Switch to alt. layout
    return

gas_switched_common:
    bcf     divemode_gaschange			; Clear flag
    tstfsz  menupos						; menupos=0?
    bra     gas_switched_common1		; No
    return								; Yes, do not switch gas (there is no Gas #0 !)
gas_switched_common1:
	movf	menupos,W					; get selected gas into WREG (1-6)

    btfsc   FLAG_ccr_mode				; in CCR mode?
	bra		gas_switched_common2		; YES - configure diluent or bailout
	btfsc   FLAG_pscr_mode				; in pSCR mode?
	bra		gas_switched_common2		; YES - configure diluent or bailout
	
	; OC
	rcall	setup_gas_registers			; With WREG = Gas 1-6
    rcall	deco_setup_oc_gases			; With WREG = Gas 1-6
	bra		gas_switched_common3

	; Loop or Bailout
gas_switched_common2:
    rcall   setup_dil_registers			; With WREG = diluent 1-6, in case of is_bailout reverts to OC gases
    rcall	deco_setup_cc_diluents		; With WREG = diluent 1-6, in case of is_bailout reverts to OC gases
 
gas_switched_common3:
    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 global event byte
    btfsc   is_bailout					; Choose OC Bailouts (OC Gases)
    bsf     bailoutgas_event			; Bailout gas change
    btfss   is_bailout					; Choose OC Bailouts (OC Gases)
	bsf		stored_gas_changed			; OC gas 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
	clrf    lo							; start with Gas0
get_first_gas_to_WREG2:
	movf    lo,W
	movf    PLUSW1,W					; Get Type of Gas #lo
	sublw   .1							; it is = 1 (First Gas)
	bz      get_first_gas_to_WREG3		; Found the first gas!
	incf    lo,F						; ++
	movlw   NUM_GAS+1
	cpfseq  lo							; All done?
	bra     get_first_gas_to_WREG2		; Not yet
	; No first gas found, use #1
	movlw   .0
	movff   WREG,opt_gas_type+0			; Set Gas1 to First
	incf	WREG,W						; 0 -> 1
	return
get_first_gas_to_WREG3:
	movf    lo,W						; Put into Wreg
	incf	WREG,W						; 0-4 -> 1-5
	return								; Done

	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
	clrf    lo							; start with Gas0
get_first_dil_to_WREG2:
	movf    lo,W
	movf    PLUSW1,W					; Get Type of Dil #lo
	sublw   .1							; it is = 1 (First Dil)
	bz      get_first_dil_to_WREG3		; Found the first dil!
	incf    lo,F						; ++
	movlw   NUM_GAS+1
	cpfseq  lo							; All done?
	bra     get_first_dil_to_WREG2		; Not yet
	; No first dil found, use #1
	movlw   .0
	movff   WREG,opt_dil_type+0			; Set Dil1 to First
	incf	WREG,W						; 0 -> 1
	return
get_first_dil_to_WREG3:
	movf    lo,W						; Put into Wreg
	incf	WREG,W						; 0-4 -> 1-5
	return								; Done

	global	deco_setup_oc_gases
deco_setup_oc_gases:					; with currently breathed gas in WREG (1-5 or 6)
	movff	WREG,char_I_current_gas		; gas to start with when doing the deco calculations

	movff   opt_gas_He_ratio+0,char_I_deco_He_ratio+0
	movff   opt_gas_O2_ratio+0,char_I_deco_O2_ratio+0
	banksel opt_gas_type+0
	movlw   .3							; 3=Deco
	cpfseq  opt_gas_type+0				; Gas is deco type?
	clrf    opt_OC_bail_gas_change+0	; No, clear depth for 0=Disabled, 1=First and 2=Travel
	banksel common

	movff   opt_gas_He_ratio+1,char_I_deco_He_ratio+1
	movff   opt_gas_O2_ratio+1,char_I_deco_O2_ratio+1
	banksel opt_gas_type+1
	movlw   .3							; 3=Deco
	cpfseq  opt_gas_type+1				; Gas is deco type?
	clrf    opt_OC_bail_gas_change+1	; No, clear depth for 0=Disabled, 1=First and 2=Travel
	banksel common

	movff   opt_gas_He_ratio+2,char_I_deco_He_ratio+2
	movff   opt_gas_O2_ratio+2,char_I_deco_O2_ratio+2
	banksel opt_gas_type+2
	movlw   .3							; 3=Deco
	cpfseq  opt_gas_type+2				; Gas is deco type?
	clrf    opt_OC_bail_gas_change+2	; No, clear depth for 0=Disabled, 1=First and 2=Travel
	banksel common

	movff   opt_gas_He_ratio+3,char_I_deco_He_ratio+3
	movff   opt_gas_O2_ratio+3,char_I_deco_O2_ratio+3
	banksel opt_gas_type+3
	movlw   .3							; 3=Deco
	cpfseq  opt_gas_type+3				; Gas is deco type?
	clrf    opt_OC_bail_gas_change+3	; No, clear depth for 0=Disabled, 1=First and 2=Travel
	banksel common

	movff   opt_gas_He_ratio+4,char_I_deco_He_ratio+4
	movff   opt_gas_O2_ratio+4,char_I_deco_O2_ratio+4
	banksel opt_gas_type+4
	movlw   .3							; 3=Deco
	cpfseq  opt_gas_type+4				; Gas is deco type?
	clrf    opt_OC_bail_gas_change+4	; No, clear depth for 0=Disabled, 1=First and 2=Travel
	banksel common

	; Setup char_I_deco_gas_change array
	movff   opt_OC_bail_gas_change+0, char_I_deco_gas_change+0
	movff   opt_OC_bail_gas_change+1, char_I_deco_gas_change+1
	movff   opt_OC_bail_gas_change+2, char_I_deco_gas_change+2
	movff   opt_OC_bail_gas_change+3, char_I_deco_gas_change+3
	movff   opt_OC_bail_gas_change+4, char_I_deco_gas_change+4

	; switch to oc mode
	movff	char_O_deco_status,lo		; working copy of char_O_deco_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_deco_status		; bank safe write-back of char_O_deco_status
		
	return

		
	global	deco_setup_cc_diluents
deco_setup_cc_diluents:					; with currently breathed gas in WREG (1-5 or 6)
	btfsc	is_bailout					; check if in bailout condition
	bra		deco_setup_oc_gases			; revert to setting up OC gases in bailout condition
	
	movff	WREG,char_I_current_gas		; gas to start with when doing the deco calculations

	movff   opt_dil_He_ratio+0,char_I_deco_He_ratio+0
	movff   opt_dil_O2_ratio+0,char_I_deco_O2_ratio+0
	movff   opt_dil_type+0,WREG			; 0=Disabled, 1=First, 2=Normal
	tstfsz  WREG						; Disabled?
	bra     $+4							; No
	movff   WREG,char_I_dil_change+0	; Yes, clear char_I_deco_gas_change (Bank safe)

	movff   opt_dil_He_ratio+1,char_I_deco_He_ratio+1
	movff   opt_dil_O2_ratio+1,char_I_deco_O2_ratio+1
	movff   opt_dil_type+1,WREG			; 0=Disabled, 1=First, 2=Normal
	tstfsz  WREG						; Disabled?
	bra     $+4							; No
	movff   WREG,char_I_dil_change+1	; Yes, clear char_I_dil_change

	movff   opt_dil_He_ratio+2,char_I_deco_He_ratio+2
	movff   opt_dil_O2_ratio+2,char_I_deco_O2_ratio+2
	movff   opt_dil_type+2,WREG			; 0=Disabled, 1=First, 2=Normal
	tstfsz  WREG						; Disabled?
	bra     $+4							; No
	movff   WREG,char_I_dil_change+2	; Yes, clear char_I_dil_change

	movff   opt_dil_He_ratio+3,char_I_deco_He_ratio+3
	movff   opt_dil_O2_ratio+3,char_I_deco_O2_ratio+3
	movff   opt_dil_type+3,WREG			; 0=Disabled, 1=First, 2=Normal
	tstfsz  WREG						; Disabled?
	bra     $+4							; No
	movff   WREG,char_I_dil_change+3	; Yes, clear char_I_dil_change

	movff   opt_dil_He_ratio+4,char_I_deco_He_ratio+4
	movff   opt_dil_O2_ratio+4,char_I_deco_O2_ratio+4
	movff   opt_dil_type+4,WREG			; 0=Disabled, 1=First, 2=Normal
	tstfsz  WREG						; Disabled?
	bra     $+4							; No
	movff   WREG,char_I_dil_change+4	; Yes, clear char_I_dil_change

	; Setup char_I_deco_gas_change array
	movff   char_I_dil_change+0, char_I_deco_gas_change+0
	movff   char_I_dil_change+1, char_I_deco_gas_change+1
	movff   char_I_dil_change+2, char_I_deco_gas_change+2
	movff   char_I_dil_change+3, char_I_deco_gas_change+3
	movff   char_I_dil_change+4, char_I_deco_gas_change+4

	; switch to CCR / pSCR mode
	movff	char_O_deco_status,lo		; working copy of char_O_deco_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_deco_status		; bank safe write-back of char_O_deco_status	
		
	return

	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
	movff	gas6_He_ratio,char_I_He_ratio	; copy gas6 H2 ratio to deco engine	
	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+0
	movff	PLUSW1,char_I_O2_ratio			; copy gas 1-5 O2 ratio to deco engine
	lfsr	FSR1,opt_gas_He_ratio+0
	movff	PLUSW1,char_I_He_ratio			; copy gas 1-5 He ratio to deco engine
setup_gas_registers_com:	
	;lfsr	FSR1,opt_gas_type				; commented out - currently not used anywhere
	;movff	PLUSW1,active_gas_type			; 0=Disabled, 1=First, 2=Travel, 3=Deco
	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 diluent 1-5 or 6 (important!)
	return

	global  setup_dil_registers
setup_dil_registers:						; with currently breathed gas in WREG (1-5 or 6)
	btfsc	is_bailout						; check if in bailout condition
	bra		setup_gas_registers				; revert to setting up OC gases in bailout condition
	movwf	active_gas						; set as current gas
	movff	WREG,active_diluent				; remember for when switching back from bailout to loop
	movlw	.6
	cpfseq	active_gas						; 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
	movff	gas6_He_ratio,char_I_He_ratio	; copy gas6 H2 ratio to deco engine
	bra		setup_dil_registers_com			; continue with common part
setup_dil_registers_15:
	decf	active_gas,W					; 1-5 -> 0-4
	lfsr	FSR1,opt_dil_O2_ratio+0
	movff	PLUSW1,char_I_O2_ratio			; copy diluent 1-5 O2 ratio to deco engine
	lfsr	FSR1,opt_dil_He_ratio+0
	movff	PLUSW1,char_I_He_ratio			; copy diluent 1-5 He ratio to deco engine
setup_dil_registers_com:
	;lfsr	FSR1,opt_dil_type				; commented out - currently not used anywhere
	;movff	PLUSW1,active_gas_type			; 0=Disabled, 1=First, 2=Normal (there is no type 3 for diluents)
	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_gas,W					; reload WREG with diluent 1-5 or 6 (important!)
	return

divemode_option_gaschange:					; Switch to the better gas
	movff	better_gas_number,menupos		; 1-5
	bsf		divemode_gaschange				; Change the gas in the dive mode loop...
	call	menuview_toggle_reset			; Reset to zero (Zero=no menuview)
	bcf		better_gas_available			; Clear flag immediately
	return

divemode_option0:							; Start/Setup Divemode menu
	call	TFT_clear_divemode_menu			; Clear menu area
	bcf	menuview
	extern	do_main_divemenu
	call	do_main_divemenu

    global  divemode_option0_return
divemode_option0_return:
;    movlw   .1
;    movwf   menupos                 ; Set to first option in divemode menu
    call    TFT_divemode_menu_cursor; Show the cursor
	movlw	divemode_menu_timeout
	movwf	timeout_counter3        ; timeout for divemode menu
    bsf     divemode_menu           ; Set flag
    clrf    menupos2                ; Clear option counter
    goto	diveloop_loop4          ; Goto back to diveloop (Menuprocessor trashes STKPTR!)

divemode_option4:
	movlw	d'58'					; two seconds left
	movwf	timeout_counter
	movlw	apnoe_timeout-1			; apnoe timeout [min]
	movwf	apnoe_timeout_counter
    btfss   simulatormode_active	; in simulator mode?
	return							; No
divemode_option1:					; Quit simulation mode
	banksel	isr_backup
    movlw   low     .1000
    movwf	sim_pressure+0
    movlw   high    .1000
	movwf   sim_pressure+1			; Set to 0m -> End of Dive
	banksel common
    call    menuview_toggle_reset   ; Reset to zero (Zero=no menuview)
	
	btfss	FLAG_apnoe_mode			; In Apnoe mode?
	return							; No
	movlw	d'58'					; two seconds left
	movwf	timeout_counter
	movlw	apnoe_timeout-1			; apnoe timeout [min]
	movwf	apnoe_timeout_counter
	return

divemode_option3:					; minus 1m
	banksel	isr_backup
	movlw	d'100'
	subwf	sim_pressure+0
	movlw	.0
	subwfb	sim_pressure+1
	rcall	divemode_simulator_check_limits
	banksel common
	return

divemode_option2:					; plus 1m
	banksel	isr_backup
	movlw	d'100'
	addwf	sim_pressure+0
	movlw	.0
	addwfc	sim_pressure+1
	rcall	divemode_simulator_check_limits
	banksel common
	return

divemode_option5:
    call    menuview_toggle_reset   ; Reset to zero (Zero=no menuview)
    bsf     reset_average_depth     ; Set Flag
    return

divemode_option6:
    bcf     divemode2                   ; Stop divetime
    movlw   .5
    addwf   divemins+0,F
    movlw   .0
    addwfc  divemins+1,F                ; Add 5 mins
    movlw   LOW     (.5*.60)
    addwf   average_divesecs+0,F
    movlw   HIGH    (.5*.60)
    addwfc  average_divesecs+1,F        ; Add 5*60 seconds
    movlw   LOW     (.5*.60)
    addwf   total_divetime_seconds+0,F
    movlw   HIGH    (.5*.60)
    addwfc  total_divetime_seconds+1,F  ; Add 5*60 seconds

	; 1. Add 300xdepth to the Sum of depths registers
    SAFE_2BYTE_COPY rel_pressure, xB	; Buffer...
    movlw   LOW     (.5*.60)
    movwf   xA+0
    movlw   HIGH    (.5*.60)
    movwf   xA+1
    call    mult16x16           		; xA*xB=xC

	movf	xC+0,w
	addwf	average_depth_hold+0,F
	movf	xC+1,w
	addwfc	average_depth_hold+1,F
	movf	xC+2,w
	addwfc	average_depth_hold+2,F
    movf	xC+3,w
	addwfc	average_depth_hold+3,F		; Will work up to 9999mbar*60*60*24=863913600mbar

	; Do the same for the _total registers (Non-Resettable)
	movf	xC+0,w
	addwf	average_depth_hold_total+0,F
	movf	xC+1,w
	addwfc	average_depth_hold_total+1,F
	movf	xC+2,w
	addwfc	average_depth_hold_total+2,F
	movf	xC+3,w
	addwfc	average_depth_hold_total+3,F; Will work up to 9999mbar*60*60*24=863913600mbar

	movlw	.5							; + 5 minutes
	movff	WREG,char_I_sim_advance_time; copy to mailbox
	bsf     divemode2                   ; continue divetime
	call	restart_deco_engine
    goto    menuview_toggle_reset		; and return...

divemode_option7:
    ; Store heading for compass view
    movff   compass_heading_shown+0,compass_bearing+0
    movff   compass_heading_shown+1,compass_bearing+1
    bsf     compass_bearing_set         ; set flag
    goto    menuview_toggle_reset       ; Done and return...
    
divemode_option8:
    bsf	    alternative_divelayout		; Set flag for mode
    bsf	    FLAG_TFT_divemode_mask_alt	; Set flag for mask
    movlw   .1
    movwf   menupos3					; For the customviews...
    call    TFT_ClearScreen				; Clear screen
    goto    menuview_toggle_reset       ; Done and return...

divemode_simulator_check_limits:
	; Check limits (150m and 0m)
	movlw	LOW		d'16000'            ; Compare to 16bar=16000mbar (150m).
	subwf   sim_pressure+0,W
	movlw	HIGH	d'16000'
	subwfb  sim_pressure+1,W
	bnc     divemode_simulator_check_limits2 ; No-carry = borrow = not deeper

	; Too deep, limit to 150m
	movlw	LOW		d'16000'
	movwf	sim_pressure+0
	movlw	HIGH	d'16000'
	movwf	sim_pressure+1
	return
divemode_simulator_check_limits2:
	movlw	LOW		d'1000'             ; Compare to 1bar == 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 0m == Ok.
	; Too shallow, limit to 0m
	movlw	LOW		d'1000'
	movwf	sim_pressure+0
	movlw	HIGH	d'1000'
	movwf	sim_pressure+1
	return

;=============================================================================
; Compare all enabled gas in list, to see if a better one is available.
;
; Output: better_gas_available, better_gas_number
;
check_gas_change:					; Checks if a better gas should be selected (by user)
	bcf		better_gas_available    ;=1: A better gas is available and a gas change is advised in divemode
	clrf	better_gas_number       ; Clear better gas register

    SAFE_2BYTE_COPY rel_pressure,xA
	movlw	d'100'
	movwf	xB+0
	clrf	xB+1
	call	div16x16				; compute depth in full m -> result in xC+0

    btfsc   FLAG_pscr_mode          ; In PSCR mode...
    bra     check_gas_change2	    ; Yes, check for diluents
    btfss   FLAG_ccr_mode           ; In CCR mode...
    bra     check_gas_change_OC_bail; No, check for OC or bailout
check_gas_change2:
    btfsc   is_bailout              ; Bailout?
    bra     check_gas_change_OC_bail; Yes, check for OC or bailout

    ; Check Diluents
    movlw   .0
    rcall   check_dil_common        ; With Gas 0-4 in WREG
    movlw   .1
    rcall   check_dil_common        ; With Gas 0-4 in WREG
    movlw   .2
    rcall   check_dil_common        ; With Gas 0-4 in WREG
    movlw   .3
    rcall   check_dil_common        ; With Gas 0-4 in WREG
    movlw   .4
    rcall   check_dil_common        ; With Gas 0-4 in WREG
    bra     check_gas_change_exit

check_gas_change_OC_bail:
    movlw   .0
    rcall   check_gas_common        ; With Gas 0-4 in WREG
    movlw   .1
    rcall   check_gas_common        ; With Gas 0-4 in WREG
    movlw   .2
    rcall   check_gas_common        ; With Gas 0-4 in WREG
    movlw   .3
    rcall   check_gas_common        ; With Gas 0-4 in WREG
    movlw   .4
    rcall   check_gas_common        ; With Gas 0-4 in WREG
;    bra     check_gas_change_exit

check_gas_change_exit:
    btfss   better_gas_available	; Is a better gas available
    bcf     blinking_better_gas		; No, Clear blinking flag
    btfss   better_gas_available	; Is a better gas available
    clrf    better_gas_number		; No, Clear better_gas_number (For gaslist display)
    bsf	    FLAG_TFT_active_gas_divemode; Redraw gas/setpoint/diluent
    return

check_gas_common:                   ; With Gas 0-4 in WREG
    btfsc   better_gas_available	; Better Gas already found?
    return                          ; Yes, return
    lfsr    FSR1,opt_gas_type       ; 0=Disabled, 1=First, 2=Travel, 3=Deco
    btfss   PLUSW1,0                ; Test for Bit0 and 1 -> type=3 -> Deco
    return                          ; No
    btfss   PLUSW1,1                ; Test for Bit0 and 1 -> type=3 -> Deco
    return                          ; No
    incf    WREG,W                  ; 1-5
    cpfseq  active_gas				; is this gas current gas?
    bra     check_gas_common2       ; No
    return                          ; Yes, skip test for active gas
check_gas_common2:
    decf    WREG,W                  ; 0-4
    movwf   hi                      ; Save tested gas 0-4
    lfsr    FSR1,opt_OC_bail_gas_change
    movff   PLUSW1,lo               ; Change depth into lo
	movlw	minimum_change_depth
	cpfsgt	lo  					; Change depth>minimum_change_depth?
	return                          ; No, Change depth not deep enough, skip!
	movf	xC+0,W					; load depth in m into WREG
	cpfsgt	lo  					; gas_change_depth < current depth?
    bra     check_gas_common3       ; No, check if we are within the better_gas_window_pos window
	incf    hi,W                    ; 1-5
	movwf	better_gas_number		; number (1-5) of the "better gas" in divemode, =0: no better gas available
	movlw	better_gas_window_neg
	subwf	lo,W                    ; Change depth-better_gas_window_neg
	cpfslt	xC+0					; current depth<Change depth-better_gas_window_neg?
    bra     check_gas_common4       ; Ok, now check the better gas ppO2<char_I_ppO2_max
    return

check_gas_common3:
	incf    hi,W                    ; 1-5
	movwf	better_gas_number		; number (1-5) of the "better gas" in divemode, =0: no better gas available
	movlw	better_gas_window_pos
	addwf	lo,W                    ; Change depth+better_gas_window_pos
	cpfsgt	xC+0					; current depth>Change depth+better_gas_window_pos?
    bra     check_gas_common4       ; Ok, now check the better gas ppO2<char_I_ppO2_max
    return

check_gas_common4:
    movf    hi,W                    	; gas 0-4 into WREG
    lfsr    FSR1,char_I_deco_O2_ratio	; load base address char_I_deco_O2_ratio array
    movff   PLUSW1,lo               	; read O2 ratio from array into lo

    SAFE_2BYTE_COPY amb_pressure, xA
	movlw	d'10'
	movwf	xB+0
	clrf	xB+1
	call	div16x16				; xC=p_amb/10
	movff	xC+0,xA+0
	movff	xC+1,xA+1
    movff   lo,xB+0                 ; =O2 ratio
	clrf	xB+1
	call	mult16x16               ; lo * p_amb/10

    ; Check very high ppO2 manually
	tstfsz	xC+2					; char_I_O2_ratio * p_amb/10 > 65536, ppO2>6,55bar?
	return                      	; Done.
    ; Check if ppO2>3,30bar
	btfsc   xC+1,7
	return                      	; Done.

    ; Check for low ppo2
	movff	xC+0,sub_b+0
	movff	xC+1,sub_b+1
	movff   char_I_ppO2_min,WREG
	mullw	d'100'		    		; char_I_ppO2_min*100
	movff	PRODL,sub_a+0
	movff	PRODH,sub_a+1
	call	subU16		    		; sub_c = sub_a - sub_b
	btfss	neg_flag
	return                      	; Done (Too low).

	;check if we are within our warning thresholds!
	movff	xC+0,sub_a+0
	movff	xC+1,sub_a+1
	movff	char_I_ppO2_max_deco,WREG	; ppO2 max for MOD calculation and color coding in divemode
	addlw   .1                  	; e.g. >1.60
	mullw	d'100'		    		; char_I_ppO2_max*100
	movff	PRODL,sub_b+0
	movff	PRODH,sub_b+1
	call	subU16		    		; sub_c = sub_a - sub_b
	btfsc	neg_flag
	bsf		better_gas_available	;=1: A better gas is available and a gas change is advised in divemode
	return                      	; Done.

check_dil_common:                   ; With Dil 0-4 in WREG
    btfsc   better_gas_available	; Better Diluent already found?
    return                          ; Yes, return
    lfsr    FSR1,opt_dil_type       ; 0=Disabled, 1=First, 2=Normal
    tstfsz  PLUSW1                  ; =0?
    bra     check_dil_common1       ; No
    return                          ; Yes, skip inactive diluents for test
check_dil_common1:
    incf    WREG,W                  ; 1-5
    cpfseq  active_gas				; is this the current diluent?
    bra     check_dil_common2       ; No
    return                          ; Yes, skip test for active diluent
check_dil_common2:
    decf    WREG,W                  ; 0-4
    movwf   hi                      ; Save tested diluent 0-4
    lfsr    FSR1,char_I_dil_change
    movff   PLUSW1,lo               ; Change depth into lo
	movlw	minimum_change_depth
	cpfsgt	lo  					; Change depth>minimum_change_depth?
	return                          ; No, Change depth not deep enough, skip!
	movf	xC+0,W					; load depth in m into WREG
	cpfsgt	lo  					; gas_change_depth < current depth?
    return                          ; No, check next gas
	incf    hi,W                    ; 1-5
	movwf	better_gas_number		; number (1-5) of the "better gas" in divemode, =0: no better gas available
	movlw	better_gas_window_neg
	subwf	lo,W                    ; Change depth-better_gas_window_neg
	cpfslt	xC+0					; current depth<Change depth-better_gas_window_neg?
	bsf		better_gas_available	;=1: A better gas is available and a gas change is advised in divemode
    return


;=============================================================================
; Check for Auto-SP
;
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:
    SAFE_2BYTE_COPY rel_pressure,xA
	movlw	d'100'
	movwf	xB+0
	clrf	xB+1
	call	div16x16				; compute depth in full m -> result in xC+0
    ; Check SP2
    btfsc   sp2_switched            ; =1: This setpoint has been autoselected already
    bra     check_dive_autosp3      ; Skip check
    movff   char_I_setpoint_change+1,lo ; Get depth in m
    tstfsz  lo                      ; =0?
    bra     check_dive_autosp2a     ; No, continue
    bra     check_dive_autosp3      ; Skip check
check_dive_autosp2a:
    decf    lo,W                    ; -1 -> WREG
    cpfsgt  xC+0                    ; Compare with depth
    bra     check_dive_autosp3      ; lower depth, do not switch
    ; auto switch to SP2
	movff	char_I_setpoint_cbar+1,char_I_const_ppO2	; Use SetPoint
    rcall   xmit_sp_set_flag
    bsf     sp2_switched            ; Set flag
check_dive_autosp3:
    ; Check SP3
    btfsc   sp3_switched            ;=1: This setpoint has been autoselected already
    bra     check_dive_autosp4      ; Skip check
    movff   char_I_setpoint_change+2,lo ; Get depth in m
    tstfsz  lo                      ; =0?
    bra     check_dive_autosp3a      ; No, continue
    bra     check_dive_autosp4      ; Skip check
check_dive_autosp3a:
    decf    lo,W                    ; -1 -> WREG
    cpfsgt  xC+0                    ; Compare with depth
    bra     check_dive_autosp4      ; lower depth, do not switch
    ; auto switch to SP3
	movff	char_I_setpoint_cbar+2,char_I_const_ppO2	; Use SetPoint
    rcall   xmit_sp_set_flag
    bsf     sp3_switched            ; Set flag
check_dive_autosp4:
    ; Check SP4
    btfsc   sp4_switched            ;=1: This setpoint has been autoselected already
    bra     check_dive_autosp5      ; Skip check
    movff   char_I_setpoint_change+3,lo ; Get depth in m
    tstfsz  lo                      ; =0?
    bra     check_dive_autosp4a     ; No, continue
    bra     check_dive_autosp5      ; Skip check
check_dive_autosp4a:
    decf    lo,W                    ; -1 -> WREG
    cpfsgt  xC+0                    ; Compare with depth
    bra     check_dive_autosp5      ; lower depth, do not switch
    ; auto switch to SP4
	movff	char_I_setpoint_cbar+3,char_I_const_ppO2	; Use SetPoint
    rcall   xmit_sp_set_flag
    bsf     sp4_switched            ; Set flag
check_dive_autosp5:
    ; Check SP5
    btfsc   sp5_switched            ;=1: This setpoint has been autoselected already
    bra     check_dive_autosp6      ; Skip check
    movff   char_I_setpoint_change+4,lo ; Get depth in m
    tstfsz  lo                      ; =0?
    bra     check_dive_autosp5a     ; No, continue
    bra     check_dive_autosp6      ; Skip check
check_dive_autosp5a:
    decf    lo,W                    ; -1 -> WREG
    cpfsgt  xC+0                    ; Compare with depth
    bra     check_dive_autosp6      ; lower depth, do not switch
    ; auto switch to SP5
	movff	char_I_setpoint_cbar+4,char_I_const_ppO2	; Use SetPoint
    rcall   xmit_sp_set_flag
    bsf     sp5_switched            ; Set flag
check_dive_autosp6:
    return

xmit_sp_set_flag:
    movff   char_I_const_ppO2,WREG
    call    transmit_setpoint       ; Transmit current setpoint from WREG (in cbar) to external electronics
    bsf     setpoint_changed        ; Set flag (For profile)
    bsf		event_occured			; Set global event byte
    return

;=============================================================================
; Setup everything to enter divemode.
;
dive_boot_oc:
    rcall   get_first_gas_to_WREG			; Gets 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	deco_setup_oc_gases				; set-up of gas list for deco calculations (with WREG = gas 1-5)
    return

dive_boot_cc:
    bcf     is_bailout                      ; =1: Bailout
    bcf     setpoint_fallback               ; =1: Fallback to SP1 due to external O2 sensor failure
    bcf		blinking_setpoint               ; Reset blinking SP flag

	; revoke sensors from usage if they do not have a valid calibration
	bsf		use_O2_sensor1
	bsf		use_O2_sensor2
	bsf		use_O2_sensor3
	btfss	sensor1_calibrated_ok
	bcf		use_O2_sensor1
	btfss	sensor2_calibrated_ok
	bcf		use_O2_sensor2
	btfss	sensor3_calibrated_ok
	bcf		use_O2_sensor3
	
	; 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_1
	movff   opt_ccr_mode,WREG				; =0: Fixed SP, =1: Sensor,  =2: Auto SP
    sublw   .2								; opt_ccr_mode = 1 (Auto SP)?
    bnz     dive_boot_cc_1
	movlw	.0
	movff	WREG,opt_ccr_mode

dive_boot_cc_1:
    bsf     setpoint_changed                ; Set flag (For profile)
    bcf     sp2_switched                    ; =1: This setpoint has been autoselected already
    bcf     sp3_switched                    ; =1: This setpoint has been autoselected already
    bcf     sp4_switched                    ; =1: This setpoint has been autoselected already
    bcf     sp5_switched                    ; =1: This setpoint has been autoselected already

    rcall   get_first_dil_to_WREG           ; get first gas (1-5) into WREG
    rcall   setup_dil_registers				; set-up of gas parameters for currently breathed gas (with WREG = current gas 1-5)
	rcall	deco_setup_cc_diluents			; set-up of gas list for deco calculations (with WREG = current gas 1-5)

	; 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
	btfss	FLAG_ccr_mode					; are we in CCR mode?
	bra		dive_boot_cc_2					; NO  - keep preloaded value
	movff	char_I_setpoint_cbar+0,WREG		; YES - get value of setpoint 1
dive_boot_cc_2:
	movff	WREG,char_I_const_ppO2			; write setpoint to deco engine
	call	transmit_setpoint				; transmit current setpoint from WREG (in cbar) to external electronics
	goto	calc_deko_divemode_sensor		; read & process sensor data (and return)

diveloop_boot:
	call	restart_set_modes_and_flags

    call    I2C_sleep_accelerometer          ; Stop accelerometer
    call    I2C_sleep_compass                ; Stop compass

	clrf	WREG
	movff	WREG,max_pressure+0				; clear some variables
	movff	WREG,max_pressure+1
	
	; init in invalid data state
	clrf	WREG							; set WREG to 0
	bsf		WREG,int_invalid_flag			; set invalid flag
	bsf		WREG,int_is_zero				; set zero flag
	movff	WREG,int_O_tank_pres_need+1		; Set flags for tank pressure needs = 0 before p2_deco.c
	movff	WREG,int_O_tank_pres_need+3		; can do it. If this is not done here and the gas needs
	movff	WREG,int_O_tank_pres_need+5		; custom view is shown before p2_deco.c completes the first
	movff	WREG,int_O_tank_pres_need+7		; deco calculation, some rubbish numbers from last dive of
	movff	WREG,int_O_tank_pres_need+9		; simulation may be shown
	
	; configure the deco engine:
	movff	char_O_deco_status,WREG			; bank-safe copy
	bsf		WREG,DECO_STATUS_0_FLAG			; configure init ...
	bsf		WREG,DECO_STATUS_1_FLAG			; ... state,
	bcf		WREG,DECO_PLAN_FLAG				; normal plan mode,
	bsf		WREG,DECO_CNS_FLAG				; enable CNS calculation (CNS at end of dive),
	bcf		WREG,DECO_VOLUME_FLAG			; disable gas volume calculation, and
	bcf		WREG,DECO_ASCENT_FLAG			; disable delayed ascent calculation
	movff	WREG,char_O_deco_status			; bank-safe copy back
	
	clrf	WREG
	movff	WREG,char_O_main_status			; reset char_O_main_status

	movlw	deco_distance
	movff	WREG,char_I_deco_distance
	movff	opt_last_stop,char_I_depth_last_deco
	movff	opt_GF_low,char_I_GF_Low_percentage
	movff	opt_GF_high,char_I_GF_High_percentage
	
    bcf     use_agf                         ; Start with normal GF set
    bcf     divemode_menu                   ; clear divemode menu flag
    
    bcf	    alternative_divelayout			; Start with default layout
	
	bcf		blinking_depth_prev				; clear flag for blinking depth	## NEW BUGFIX
	bcf		blinking_depth_warning			; clear flag for blinking depth	## NEW BUGFIX
	bcf		blinking_depth_toggle			; clear flag for blinking depth	## NEW BUGFIX
	
	movlw	d'1'
	movwf	apnoe_max_pressure+0
	clrf	apnoe_max_pressure+1
;	clrf	apnoe_surface_mins
;	clrf	apnoe_surface_secs		
	clrf	apnoe_mins
	clrf	divemins+0
	clrf	divemins+1
    
	; Copy date and time for logbook
    movff   year,start_year
    movff   month,start_month
    movff   day,start_day
    movff   hours,start_hours
    movff   mins,start_mins
    
    movff   int_O_CNS_fraction+0,CNS_start+0	; save CNS value at beginning of dive
    movff   int_O_CNS_fraction+1,WREG			; get high byte to WREG
	bcf		WREG,int_warning_flag				; clear warning flag bit
	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)

    bcf     no_more_divesecs            		; =1: do no longer show seconds in divemode
	bcf		divemode_menu_active
    clrf    menupos
    clrf    menupos2                    		; Reset to zero (Zero=no premenu or simulator task)
	bsf		sensors_agree						; init of sensors disagree warning system
	
    btfsc   FLAG_ccr_mode
    bra	    diveloop_boot_cc
    btfsc   FLAG_pscr_mode
    bra	    diveloop_boot_cc
    rcall   dive_boot_oc
    bra	    diveloop_boot_cont

diveloop_boot_cc:
    rcall	dive_boot_cc
	
diveloop_boot_cont:
    ; Copy opt_dil_types into backup (For "lost gas" feature)
    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+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+4,opt_dil_type_backup+4    				; 0=Disabled, 1=First, 2=Normal
    ; 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+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+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
    ; Also copy change depths into backup (For "lost gas" feature)
    movff   char_I_dil_change+0,opt_dil_change_backup+0				; Gas change depths Diluents
    movff   char_I_dil_change+1,opt_dil_change_backup+1				; Gas change depths Diluents
    movff   char_I_dil_change+2,opt_dil_change_backup+2				; Gas change depths Diluents
    movff   char_I_dil_change+3,opt_dil_change_backup+3				; Gas change depths Diluents
    movff   char_I_dil_change+4,opt_dil_change_backup+4				; Gas change depths Diluents
    ; Also copy change depths into backup (For "lost gas" feature)
    movff   opt_OC_bail_gas_change+0,opt_OC_bail_gas_change_backup+0; Gas change depths OC/Bailout
    movff   opt_OC_bail_gas_change+1,opt_OC_bail_gas_change_backup+1; Gas change depths OC/Bailout
    movff   opt_OC_bail_gas_change+2,opt_OC_bail_gas_change_backup+2; Gas change depths OC/Bailout
    movff   opt_OC_bail_gas_change+3,opt_OC_bail_gas_change_backup+3; Gas change depths OC/Bailout
    movff   opt_OC_bail_gas_change+4,opt_OC_bail_gas_change_backup+4; Gas change depths OC/Bailout

	clrf	better_gas_number           ; Clear better gas register

	bcf		show_safety_stop			; =1: Show the safety stop
	clrf	safety_stop_countdown		; Clear count-down

 	clrf	samplesecs
	clrf	apnoe_timeout_counter		; timeout in minutes
	clrf 	timeout_counter				; takes care of the timeout (Low byte)
	clrf 	timeout_counter2			; takes care of the timeout (High byte)
	clrf	AlarmType					; Clear all alarms
	bcf		event_occured				; clear flag
	clrf	average_depth_hold_total+0
	clrf	average_depth_hold_total+1
	clrf	average_depth_hold_total+2
	clrf	average_depth_hold_total+3	; Clear Non-Resettable Average
    rcall	reset_average1				; Reset the resettable average depth
    bcf		decostop_active
	bcf		better_gas_available        ; =1: A better gas is available and a gas change is advised in divemode
	call	ghostwriter_short_header	; Write short header with divenumber into profile memory

    btfsc   simulatormode_active
    bra     diveloop_boot_1
    ; Normal mode = Surface pressure is the pressure 30mn before dive.
	SAFE_2BYTE_COPY last_surfpressure_30min, int_I_pres_surface	;copy surfacepressure to deco routine
	SAFE_2BYTE_COPY last_surfpressure_30min, last_surfpressure	;copy surfacepressure to last_surfpressure for correct depth
    bra     diveloop_boot_2

diveloop_boot_1:
    ; Simulator mode: Surface pressure is 1bar.
    movlw   LOW .1000
	movff	WREG,int_I_pres_surface+0   	; LOW copy surfacepressure to deco routine
    movlw   HIGH .1000
	movff	WREG,int_I_pres_surface+1   	; HIGH copy surfacepressure to deco routine

diveloop_boot_2:
	SAFE_2BYTE_COPY	temperature,minimum_temperature ; Reset Min-Temp registers

; Init profile recording parameters	
	movff	samplingrate,samplesecs_value	; to avoid EEPROM access in the ISR
	movlw	div_temperature
	movwf	divisor_temperature         	; load divisors for profile storage
	movlw	div_deco
	movwf	divisor_deco				
	movlw	div_gf
	movwf	divisor_gf
	movlw	div_ppo2_sensors
	movwf	divisor_ppo2_sensors
	movlw	div_decoplan
	movwf	divisor_decoplan
	movlw	div_cns
	movwf	divisor_cns
	movlw	div_tank
	movwf	divisor_tank

	btfss	FLAG_apnoe_mode					; In Apnoe mode?
	bra		divemode_boot1

	; Overwrite some parameters in Apnoe mode....
	movlw	samplingrate_apnoe
	movwf	samplesecs_value				; to avoid EEPROM access in the ISR

divemode_boot1:
    bsf     ccr_diluent_setup				; For CCR mode (Required to have better gas working)
    btfsc   FLAG_ccr_mode               	; =1: CCR mode (Fixed ppO2 or Sensor) active
    bra     divemode_boot2
    btfsc   FLAG_pscr_mode
    bra     divemode_boot2
    
    ; in OC Mode, disable ppO2 logging
    movlw   .0
    movwf   divisor_ppo2_sensors
    
    bcf     ccr_diluent_setup				; For OC mode (Required to have better gas working)

divemode_boot2:
	bcf		LEDg
	bcf		LEDr
	bcf		realdive
	btfss	simulatormode_active			; do not disable in simulator mode!					
	call	disable_rs232					; Disable RS232
    btfsc   enable_screen_dumps         	; =1: Ignore vin_usb, wait for "l" command (Screen dump)
    call	enable_rs232					; Also sets to speed_normal ...
    ; Reset divetime seconds
    movlw   .2                          	; Start at 2seconds
    movwf   total_divetime_seconds+0
    clrf    total_divetime_seconds+1
    movwf   divesecs
    movwf   apnoe_secs
    bsf	    divemode2                   	; displayed divetime is running (Divetime starts HERE)
    return									; Done with divemode boot

divemode_check_for_warnings:
    movlw   .1				    			; One warning at a time in alt. layout mode
    btfss   alternative_divelayout  
    movlw   .2				    			; Two warnings at a time in default layout mode
    cpfsgt  warning_counter		    		; only one (or two) warnings active?
    bra     divemode_check_for_warnings1    ; Yes, update every second

    btfss   secs,0                      	; Every two seconds...
    return
    btfss   secs,1                      	; Every four seconds...
    return

divemode_check_for_warnings1:
	bcf		warning_active						; Clear flag
	clrf	warning_counter						; Clear counter

	; warnings sorted by severity, highest severity first
	
    ; Warnings for all modes
    call	check_warn_battery                  ; Check if the battery level should be displayed/warned
    call    check_divetimeout                   ; Not actually a warning. Check and show the divemode timeout

	btfsc	FLAG_apnoe_mode             		; Done for Apnoe or Gauge mode
    bra     divemode_check_for_warnings2
	btfsc	FLAG_gauge_mode             		; Done for Apnoe or Gauge mode
	bra     divemode_check_for_warnings2

    ; Warnings 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?
	rcall	check_warn_sensors_disagree			; NO  - further evaluate
	btfsc	sensors_agree						; are the sensor values within the threshold range?
	bcf		sensor_warning						; YES - revoke memorized sensor warning

	movff	char_O_deco_warnings,WREG			; bank-safe copy for deco warnings
	btfsc	WREG,outside_warning_lock			; are we outside of the ZH-L16 model?
	rcall	warn_outside						; YES
	
	rcall	check_IBCD							; check for IBCD attention or warning
	
	btfsc	decostop_active						; In deco mode?
	rcall	check_and_store_gf_violation		; Yes, sets warnings, if required

	movff	char_O_deco_warnings,WREG			; bank-safe copy for deco warnings
	btfsc	WREG,mbubble_warning_lock			; do we have a microbubbles warning?
	rcall	warn_mbubbles						; YES
	
	rcall	check_cns_violation					; Check CNS value and display it, if required	
	
	;btfsc	decostop_active						; In deco mode?
	rcall	check_gas_needs						; show gas needs warning if any gas need is > threshold

	rcall	check_eod_cns_violation				; Check CNS values for end-of-dive and display warning, if required
	
    call    TFT_display_ftts					; Show @+x time
	
    btfsc   use_agf                             ; In aGF mode?
    rcall   warn_agf                            ; Yes, show a warning for it

    btfsc   setpoint_fallback                   ; =1: Fallback to SP1 due to external O2 sensor failure
    rcall   warn_fallback                       ; Show the warning
	
divemode_check_for_warnings2:
; Display the warning icon?
	btfsc	warning_active						; Any warning active?
	bsf	FLAG_TFT_divemode_warning				; Yes
	btfss	warning_active						; Any warning active?
	bsf	FLAG_TFT_divemode_warning_clear			; No, clear warning icon

; Setup warning_page number
    incf    warning_page,F
    movf    warning_page,W
    bcf     STATUS,C
    btfss   alternative_divelayout
    rlcf    warning_page,W                      ; *2 (But only in standard layout mode)
    cpfsgt  warning_counter                     ; > warning_counter
    clrf    warning_page                        ; No, clear
	
; Clear both rows of warnings if there is nothing to show at all
	tstfsz	warning_counter						; any warnings?
	bra	divemode_check_for_warnings3			; YES - look if second row needs to be cleared
	bsf	FLAG_TFT_dive_warning_text_clear		; Set flag
	return
divemode_check_for_warnings3:
	
	
; Clear 2nd row of warnings if there is nothing to show (on this page)
    btfss   second_row_warning                  ; =1: The second row contains a warning
    bsf	    FLAG_TFT_dive_warning_text_clr2	; Set flag for 2nd row
    return                                      ; Done.

    global  check_warn_battery
check_warn_battery:
    movff   batt_percent,lo
    movlw	battery_show_level+1
    cpfslt	lo
    return                              		; No Display, no warning
    ; Display Battery, but warn?
    movff	batt_percent,lo
    movlw	color_code_battery_low+1
    cpfsgt	lo                          		;
    bsf		warning_active						; Set Warning flag
    
    movlw   .4
    cpfseq  menupos3            				; battery shown in Custom View 4?
    bra     check_warn_battery2					; No
    return                     					; Yes, do not show twice (in custom view and in warning area)
check_warn_battery2:
    incf	warning_counter,F					; increase counter
    goto	TFT_update_batt_percent_divemode	; Show percent (And return)

check_divetimeout:
    btfsc		divemode2				
    return										; displayed divetime is not running
	incf	warning_counter,F					; increase counter
    goto    TFT_divetimeout						; Show timeout counter  (and return)


check_ppO2:
	btfsc   FLAG_ccr_mode 				; are we in CCR mode?
	bra		check_ppO2_loop				; YES
	btfsc	FLAG_pscr_mode				; are we in pSCR mode?
	bra		check_ppO2_loop				; YES
	bra		check_ppO2_oc_1				; NO  - neither CCR nor pSCR
check_ppO2_loop:
	btfsc	is_bailout					; in bailout?
	bra		check_ppO2_oc_1				; YES - continue with OC
	movff	int_O_pure_ppO2+1,hi		; NO  - get upper part of int_O_pure_ppO2
	btfsc	hi,int_warning_flag			; 		ppO2 of the pure diluent to low or high? 
	rcall	check_ppO2_d				; 		YES - show warning and return on next line
	bra		check_ppO2_oc_2				;		      skip pre-warning threshold test on breathed ppO2
check_ppO2_oc_1:
	movff	int_O_breathed_ppO2+1,WREG	; get upper part of int_O_breathed_ppO2
	btfsc	WREG,int_prewarning_flag	; breathed ppO2 just above pre-warning threshold?
	bra		check_ppo2_display			; YES - show ppO2
check_ppO2_oc_2:
	movff	int_O_breathed_ppO2+1,WREG	; get upper part of int_O_breathed_ppO2 (perhaps again)
	btfsc	WREG,int_low_flag			; breathed ppO2 to low?
	bra		check_ppO2_low				; YES - record the warning and show ppO2
	btfsc	WREG,int_high_flag			; breathed ppO2 to 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
	bra		check_ppo2_display			; YES - just show ppO2
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
	bsf		event_occured				; set event   flag
	bsf		warning_active				; set warning flag
	btfsc	is_bailout					; are we in bailout?
	bra		check_ppo2_display			; YES - skip CCR/pSCR checks
	btfsc   FLAG_ccr_mode 				; are we in CCR mode?
	return								; YES - no extra warning required
	btfsc	FLAG_pscr_mode				; are we in pSCR mode?
	return								; YES - no extra warning required
check_ppo2_display:						; display warning if ppO2 is not already shown in custom view
    movlw   .9
    cpfseq  menupos3            		; ppO2 shown in Custom View 9?
    bra     check_ppO2_a        		; No
    return                      		; Yes, do not show twice (in custom view and in warning area)
check_ppO2_a:
    movlw   .11
    cpfseq  menupos3            		; ppO2 shown in Custom View 11?
    bra     check_ppO2_b        		; No
    return                      		; Yes, do not show twice (in custom view and in warning area)
check_ppO2_b:
    movlw   .12
    cpfseq  menupos3            		; ppO2 shown in Custom View 12?
    bra     check_ppO2_c        		; No
    return                      		; Yes, do not show twice (in custom view and in warning area)
check_ppO2_c:
    movlw   .10
    cpfseq  menupos3            		; ppO2 shown in Custom View 10?
    bra     check_ppO2_d				; No
    return                      		; Yes, do not show twice (in custom view and in warning area)
check_ppO2_d:    
    incf	warning_counter,F			; increase counter
    goto    TFT_display_ppo2			; show breathed gas or diluent ppO2 warning (and return)
	

    global  check_cns_violation
check_cns_violation:
    ; Check if CNS should be displayed
    movff   int_O_CNS_fraction+1,WREG	; get high byte
    btfsc	WREG,int_warning_flag		; warning flag set?
    bra     check_cns_violation2		; Yes - issue warning
	btfsc	WREG,int_prewarning_flag	; pre-warning flag set?
	bra		display_cns_violation		; YES - just display CNS
	return                              ; No  - no display, no warning
check_cns_violation2:
	bsf		warning_active				; Set Warning flag
display_cns_violation:					; Show CNS if not shown in the custom view
	movlw   .11
	cpfseq  menupos3					; CNS shown in Custom View?
	bra     display_cns_violation2      ; No
    return								; Yes, do not show twice (in custom view and in warning area)
display_cns_violation2:
	movlw   .8
	cpfseq  menupos3					; CNS shown through Custom View 8 right now?
	bra     display_cns_violation3      ; No
    return								; Yes, do not show twice (in custom view and in warning area)
display_cns_violation3:
	incf	warning_counter,F	    	; increase counter
    goto	TFT_display_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
    btfsc	WREG,int_warning_flag       ; current CNS value in warning state?
    return								; YES - inhibit eod warning if current CNS is already in warning
    movff   int_O_normal_CNS_fraction+1,WREG
	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
	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:				; YES - issue warning
	bsf		warning_active				; set Warning flag
	movlw   .8							; issue textual warning if CNS values are not shown in the custom view right now
	cpfseq  menupos3					; CNS values shown through Custom View 8 right now?
	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	warning_counter,F	    	; increase counter
    goto	TFT_display_eod_cns			; issue CNS at end-of-dive warning (and return)


    global  check_and_store_gf_violation
check_and_store_gf_violation:
	movff	int_O_gradient_factor+1,WREG	; get upper byte of gradient factor
	btfss	WREG,int_warning_flag			; check if the warning flag is set
	bra     check_and_store_gf_violation2   ; NO  - continue with checking for pre-warning
	movlw	d'2'                        	; YES - set type of alarm
	movwf	AlarmType                   	; 		copy to alarm register
	bsf		event_occured               	; 		set event   flag
	bsf		warning_active              	; 		set warning flag
	bra		check_and_store_gf_violation3	;		show gf warning
check_and_store_gf_violation2:
	btfsc	WREG,int_prewarning_flag		; check if the pre-warning flag is set
    bra		check_and_store_gf_violation3	; YES - show gf
	TSTOSS	opt_enable_IBCD					; NO  - IBCD warning activated?
	bra		check_and_store_gf_violation4	; 		NO  - continue checking of deco info
	movff	char_O_deco_warnings,WREG		; 		YES - get the deco warnings vector
	btfss	WREG,IBCD_warning				; 			  is the IBCD warning flag set?
	bra		check_and_store_gf_violation4	; 			  NO  - continue checking for deco info
check_and_store_gf_violation3:				;			  YES - show gf
	bsf		warning_active					; set Warning flag
	incf	warning_counter,F				; increase counter
    goto    TFT_warning_gf              	; show GF (and return)
check_and_store_gf_violation4:				; check for deco info
	btfss	divemode						; in divemode?
	return									; NO  - done, return
	movff	char_O_deco_warnings,WREG		; YES - get the deco warnings vector
	btfss	WREG,deco_flag					; 		check if the deco flag is set
    return									; 		NO  - all done, return
	incf	warning_counter,F				; 		YES - increase counter
    goto    TFT_info_deco	             	; 			  show deco info
	
	
warn_outside:
	incf	warning_counter,F			; increase counter
	bsf		warning_active              ; Set Warning flag
    goto    TFT_warning_outside			; show microbubbles warning (and return)

	
	global	warn_mbubbles
warn_mbubbles:
	incf	warning_counter,F			; increase counter
	bsf		warning_active              ; Set Warning flag
    goto    TFT_warning_mbubbles		; show microbubbles warning (and return)
	
warn_agf:
	incf	warning_counter,F			; increase counter
	goto    TFT_warning_agf             ; Show aGF warning  (and return)

warn_fallback:
    incf	warning_counter,F			; increase counter
    bsf		warning_active              ; Set Warning flag
	goto    TFT_warning_fallback        ; Show fallback warning  (and return)

	
check_gas_needs:
	banksel	int_O_tank_pres_need
	movf	int_O_tank_pres_need+1,w	; get 				HIGH(pres need of 1st tank)
	iorwf	int_O_tank_pres_need+3,w	; inclusive or with HIGH(pres need of 2nd tank)
	iorwf	int_O_tank_pres_need+5,w	; inclusive or with HIGH(pres need of 3rd tank)
	iorwf	int_O_tank_pres_need+7,w	; inclusive or with HIGH(pres need of 4th tank)
	iorwf	int_O_tank_pres_need+9,w	; inclusive or with HIGH(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		; NO  - check if any gas has a pres_need >= pres_fill
	bsf		warning_active				; YES - set warning flag
	btfsc	WREG,int_warning_flag		; NO  - check if any gas has a pres_need >= pres_fill
	goto	TFT_warning_gas_needs_warn	; Yes - show a warning
	btfsc	WREG,int_prewarning_flag	; NO  - check if any gas has a pres_need >= pres_fill * threshold
	goto	TFT_warning_gas_needs_att	; YES - show an attention
	bcf		gas_needs_attention			; NO  - clear flag for a new attention
	bcf		gas_needs_warning			;       clear flag for a new warning
	return

	
check_warn_sensors_disagree:
    incf	warning_counter,F			; increase counter
	bsf		warning_active				; YES - set Warning flag
	goto	TFT_warning_sensor_disagree	; 		show sensor disagree warning (and return)


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	warning_counter,F			; 		YES - increase counter
	goto	TFT_warning_IBCD			;			  write warning to display
	


	global	restart_deco_engine
	global	restart_deco_engine_wo_ceiling
restart_deco_engine:
	; make bank save copies and set flags for invalid data
	movff	int_O_ceiling+1,WREG
	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:
	; make more bank save copies and set more flags for invalid data
	movff	char_O_deco_gas+0,WREG
	bsf		WREG,char_invalid_flag
	movff	WREG,char_O_deco_gas+0

	movff	int_O_ascenttime+1,WREG
	bsf		WREG,int_invalid_flag
	movff	WREG,int_O_ascenttime+1

	movff	int_O_alternate_ascenttime+1,WREG
	bsf		WREG,int_invalid_flag
	movff	WREG,int_O_alternate_ascenttime+1

	movff	int_O_normal_CNS_fraction+1,WREG
	bsf		WREG,int_invalid_flag
	movff	WREG,int_O_normal_CNS_fraction+1

	movff	int_O_alternate_CNS_fraction+1,WREG
	bsf		WREG,int_invalid_flag
	movff	WREG,int_O_alternate_CNS_fraction+1

	movff	int_O_tank_pres_need+1,WREG
	bsf		WREG,int_invalid_flag
	movff	WREG,int_O_tank_pres_need+1
	
	; restart deco engine
	movff	char_O_deco_status,WREG			; get current deco engine configuration
	bcf		WREG,DECO_STATUS_0_FLAG			; set status flags to...
	bcf		WREG,DECO_STATUS_1_FLAG			; ... DECO_STATUS_START
	bsf		WREG,DECO_PLAN_FLAG				; fake we came from alternative plan to force normal plan to be done next
	movff   WREG,char_O_deco_status 		; write back new configuration to restart deco computations

    return
	
	
 END