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view src/rx_ops.asm @ 622:02d1386429a6
0x60 added for (future) option to change logbook offset via PC/Bluetooth
| author | heinrichsweikamp |
|---|---|
| date | Wed, 10 Apr 2019 10:51:07 +0200 |
| parents | ca4556fb60b9 |
| children | c40025d8e750 |
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;============================================================================= ; ; File rx_ops.asm V2.99c ; ; RX (Tank Pressure Transmitter) Routines. ; ; Copyright (c) 2018, heinrichs weikamp, all right reserved. ;============================================================================= #include "hwos.inc" ; mandatory header #include "shared_definitions.h" ; mailbox to p2_deco.c #include "i2c.inc" #include "math.inc" #include "isr.inc" extern get_first_gas_to_WREG extern get_first_dil_to_WREG ; SAC calculation averaging settings #DEFINE time_accu_target_OC .60 ; [s] target time accumulator filling level in OC modes #DEFINE time_accu_target_CCR .180; [s] target time accumulator filling level in CCR mode rx_ops CODE IFDEF _rx_functions ;============================================================================= ; Get configured pressure readings ; ; input : opt_TR_1st_pres - selector for first pressure reading, in normal mode ; opt_TR_Bail_pres - selector for first pressure reading, in bailout mode ; opt_TR_2nd_pres - selector for second pressure reading, all modes ; ; output: int_IO_pressure_value+0/+2 - pressure in 0.1 bar, low byte ; int_IO_pressure_value+1/+3 - pressure in 0.1 bar, high byte, including data not available flag ; char_I_pressure_gas +0/+1 - associated gas (1-5) / diluent (6-10) ; char_I_pressure_age +0/+1 - age of data in seconds (max 60) ; char_I_pressure_stat +0/+1 - status data ; global get_pressure_readings get_pressure_readings: call I2C_get_tankdata ; get raw pressure data get_pressure_readings_1: movff opt_TR_1st_pres,ul ; 1st pressure to read btfsc FLAG_bailout_mode ; in bailout mode? movff opt_TR_Bail_pres,ul ; YES - replace with assigned bailout selection tstfsz ul ; disabled? bra get_pressure_readings_1a ; NO - get received pressure data rcall get_pressure_readings_H1 ; YES - set pressure data to not available bra get_pressure_readings_1c ; - continue with copying to result vars get_pressure_readings_1a: movlw .11 ; first code for "special" pressures cpfslt ul ; opt_TR_1st_pres < 11 ? rcall get_pressure_readings_H2 ; NO - pre-process measurement selection rcall get_pressure_readings_H3 ; get transmitter ID rcall get_pres_by_transmitter_id ; get data from transmitter with ID in hi:lo into hi:lo (pressure) and up (status) get_pressure_readings_1c: movff lo,int_IO_pressure_value+0 ; copy pressure, low byte movff hi,int_IO_pressure_value+1 ; copy pressure, high byte movff ul,char_I_pressure_gas+0 ; copy associated gas number movff up,char_I_pressure_age+0 ; copy age of data movff ex,char_I_pressure_stat+0 ; copy status data get_pressure_readings_2: movff opt_TR_2nd_pres,ul ; 2nd pressure to read tstfsz ul ; disabled? bra get_pressure_readings_2a ; NO - get received pressure data rcall get_pressure_readings_H1 ; YES - set pressure data to not available bra get_pressure_readings_2c ; - continue with copying to result vars get_pressure_readings_2a: movlw .11 ; first code for "special" pressures cpfslt ul ; opt_TR_2nd_pres < 11 ? rcall get_pressure_readings_H2 ; NO - pre-process measurement selection btfss ul,7 ; gas selector >= 127 (special treatment)? bra get_pressure_readings_2b ; NO - proceed reading a pressure rcall get_pressure_readings_H1 ; YES - set pressure data to not available bra get_pressure_readings_2c ; - continue wit copying to output data get_pressure_readings_2b: rcall get_pressure_readings_H3 ; get transmitter ID rcall get_pres_by_transmitter_id ; get data from transmitter with ID in hi:lo into hi:lo (pressure) and up (status) get_pressure_readings_2c: movff lo,int_IO_pressure_value+2 ; copy pressure, low byte movff hi,int_IO_pressure_value+3 ; copy pressure, high byte movff ul,char_I_pressure_gas+1 ; copy associated gas number movff up,char_I_pressure_age+1 ; copy age of data movff ex,char_I_pressure_stat+1 ; copy status data return get_pressure_readings_H1: clrf lo ; set pressure to 0 (low byte) clrf hi ; set pressure to 0 (high byte) clrf up ; set age to 0 clrf ex ; set status to 0 bsf hi,int_not_avail_flag ; set flag for data not available return get_pressure_readings_H2: movlw .11 subwf ul,F bnz get_pressure_readings_H2a call get_first_gas_to_WREG ; ul = 11 -> ul = (get_first_gas_to_WREG) movwf ul return get_pressure_readings_H2a: decfsz ul,F bra get_pressure_readings_H2b movff active_gas,ul ; ul = 12 -> ul = active_gas return get_pressure_readings_H2b: decfsz ul,F bra get_pressure_readings_H2c call get_first_dil_to_WREG ; ul = 13 -> ul = (get_first_dil_to_WREG) + 5 movwf ul movlw .5 addwf ul,F return get_pressure_readings_H2c: decfsz ul,F bra get_pressure_readings_H2d movff active_dil,ul ; ul = 14 -> ul = active_dil + 5 movlw .5 addwf ul,F return get_pressure_readings_H2d: movlw .1 movwf ul ; ul >= 15 -> should not happen, default to ul = 1 return get_pressure_readings_H3: lfsr FSR1,opt_transmitter_id_1 ; load base address of transmitter ID array decf ul,W ; (1-10) -> (0-9) mullw .2 ; IDs are 2 byte in size movf PRODL,W ; WREG is index now movff PLUSW1,lo ; get transmitter ID (low byte) incf WREG,W ; increment index movff PLUSW1,hi ; get transmitter ID (high byte) return ;============================================================================= ; Get data from transmitter with ID in (hi:lo) ; ; input: hi:lo = transmitter ID ; ; output: hi:lo = pressure in 0.1 bar if return code = 0, else 0 + int_not_avail_flag ; up = packet age if return code = 0, else 0 ; ex = status data if return code = 0, else 0 ; ; return code: 0 transmitter found ; 254 illegal transmitter ID ; 255 transmitter not found ; ; RX slot data: Byte 0 : transmitter ID high byte ; 1 : transmitter ID low byte ; 2 (-> hi) : pressure in 0.1 bar, high byte ; 3 (-> lo) : pressure in 0.1 bar, low byte ; 4 (-> ex) : status data: ; bit 2..0: battery status ; 5..3: sequence counter ; 6: =1 if pressure changed (usage in RX slot data) ; =1 if transmitter not found (usage in output data) ; 7: =1 if pressure sensed (usage in RX slot data) ; =1 if low battery (< 3.0V) (usage in output data) ; 5 (-> up) : age of data in seconds, 0 if slot is unused ; global get_pres_by_transmitter_id get_pres_by_transmitter_id: ; hi:lo zero? tstfsz hi ; hi <> zero ? bra output_pressure_1 ; YES - search transmitter tstfsz lo ; lo <> zero ? bra output_pressure_1 ; YES - search transmitter movlw .254 ; NO to both - set return code for invalid transmitter ID bra output_pressure_6 ; - clear result vars, set data as not available and return output_pressure_1: lfsr FSR1,rx_buffer ; load base address of RX buffer movlw .8 ; 8 RX slots to look at movwf up ; up will be the loop counter output_pressure_2: movf POSTINC1,W ; get high byte of received transmitter ID cpfseq hi ; match? bra output_pressure_3 ; NO - check next slot movf POSTINC1,W ; get low byte byte received transmitter ID cpfseq lo ; match? bra output_pressure_4 ; NO - check next slot ; transmitter found, gather data ; YES - transmitter found, copy: movff POSTINC1,hi ; - pressure high byte, movff POSTINC1,lo ; - pressure low byte, movff POSTINC1,ex ; - status byte, and movff POSTINC1,up ; - packet age. movlw rx_packet_overdue_timeout ; - load overdue time subwf up,W ; - subtract overdue time from packet age btfss STATUS,N ; - result negative (packet younger than overdue time)? bsf hi,int_outdated_flag ; NO - set outdated flag bcf ex,char_transmitter_lost ; - clear transmitter lost flag bsf ex,char_transmitter_low_bat ; - set low battery warning by default btfsc ex,1 ; - bit 1 of battery voltage set? bcf ex,char_transmitter_low_bat ; - YES - revoke low battery warning btfsc ex,2 ; - bit 2 of battery voltage set? bcf ex,char_transmitter_low_bat ; - YES - revoke low battery warning ;bsf ex,char_transmitter_low_bat ; DEBUG CODE TO FAKE A LOW BAT WARNING retlw .0 ; - return with success code 0 output_pressure_3: movf POSTINC1,W ; dummy read to advance FSR0 to byte 2 position output_pressure_4: dcfsnz up,F ; decrement loop counter, last slot searched? bra output_pressure_5 ; YES - return with error code movf POSTINC1,W ; NO - dummy reads to advance FSR0 to byte 3 (any other code would not be more compact...) movf POSTINC1,W ; - ... byte 4 movf POSTINC1,W ; - ... byte 5 movf POSTINC1,W ; - ... byte 6 = first byte of next slot bra output_pressure_2 ; - loop output_pressure_5: movlw .255 ; return code for transmitter not found clrf ex ; clear ex (status data) bsf ex,char_transmitter_lost ; set transmitter status to lost bra output_pressure_7 output_pressure_6: clrf ex ; clear ex (status data) output_pressure_7: clrf lo ; clear lo (pressure, low byte) clrf hi ; clear hi (pressure, high byte) clrf up ; clear up (age of data) bsf hi,int_not_avail_flag ; set flag for data not available return ; done ;============================================================================= ; Get transmitter ID in given slot ; ; input : WREG = slot (0-7) ; output : hi:lo = transmitter ID ; global get_transmitter_id_by_slot get_transmitter_id_by_slot: lfsr FSR1,rx_buffer ; load base address of RX buffer mullw .6 ; multiply WREG with 6 because each slot is 6 bytes in size movf PRODL,W ; get result into WREG to be used as index (product is 42 at max) movff PLUSW1,hi ; read transmitter ID high byte incf WREG,W ; increment index movff PLUSW1,lo ; read transmitter ID low byte return ;============================================================================= ; Compute average pressure drop from 1st / 2nd reading ; ; Memory Map: ; ------------------------------------------------------------------------------------ ; ; pres_accu_1st res 4 ; accumulator for pressure drop in 1/(160 * 2^16) bar ; pres_accu_2nd res 4 ; accumulator for pressure drop in 1/(160 * 2^16) bar ; time_accu_1st res 1 ; accumulator for reading periods in seconds ; gas__last_1st res 1 ; last gas assignment ; time_accu_2nd res 1 ; accumulator for reading periods in seconds ; gas__last_2nd res 1 ; last gas assignment ; pres_last_1st res 2 ; last pressure reading pressure in 1/160 bar ; pres_last_2nd res 2 ; last pressure reading pressure in 1/160 bar ; time_last_1st res 2 ; last pressure reading time in seconds ; time_last_2nd res 2 ; last pressure reading time in seconds ; ; int_IO_pressure_value [1] res 2 ; current pressure reading in 1/10 bar ; int_IO_pressure_value [2] res 2 ; current pressure reading in 1/10 bar ; int_I_pressure_drop [1] res 2 ; calculated average pressure drop in 1/5120 bar/sec ; int_I_pressure_drop [2] res 2 ; calculated average pressure drop in 1/5120 bar/sec ; relative positioning of 16 bit ASM variables #DEFINE offset_FSR1_time_accu .0 ; offset 0 == base address of 1st/2nd #DEFINE offset_FSR1_gas__last .1 ; offset 1 to base address of 1st/2nd #DEFINE offset_FSR1_pres_last .4 ; offset 4 ... #DEFINE offset_FSR1_time_last .8 ; offset 8 ... ; relative positioning of shared integer variables #DEFINE offset_FSR2_press_curr .0 ; offset 0 == base address of 1st/2nd #DEFINE offset_FSR2_press_drop .4 ; offset 4 to base address of 1st/2nd calc_pres_drop_1st: ; set up base addresses lfsr FSR0,pres_accu_1st-1 ; load base address - 1 of pressure accumulator lfsr FSR1,time_accu_1st ; load base address of other ASM variables lfsr FSR2,int_IO_pressure_value+0; load base address of the shared variables ; get the currently assigned gas into lo movff char_I_pressure_gas+0,lo ; get the age of the current reading into hi movff char_I_pressure_age+0,hi ; continue with common part bra calc_pres_drop_common calc_pres_drop_2nd: ; set up base addresses lfsr FSR0,pres_accu_2nd-1 ; load base address - 1 of pressure accumulator lfsr FSR1,time_accu_2nd ; load base address of other ASM variables lfsr FSR2,int_IO_pressure_value+2; load base address of the shared variables ; get the currently assigned gas into lo movff char_I_pressure_gas+1,lo ; get the age of the current reading into hi movff char_I_pressure_age+1,hi calc_pres_drop_common: ; load the pressure accumulator into xC - FSR0 has been initialized to base address -1 movff PREINC0,xC+0 ; copy pressure accumulator to xC, lowest byte movff PREINC0,xC+1 ; copy pressure accumulator to xC, second byte movff PREINC0,xC+2 ; copy pressure accumulator to xC, third byte movff PREINC0,xC+3 ; copy pressure accumulator to xC, highest byte ; check if the assigned gas has changed movlw offset_FSR1_gas__last ; load index of last assigned gas movf PLUSW1,W ; copy last gas to WREG cpfseq lo ; is current gas = last gas ? bra calc_pres_drop_reset ; NO - reset everything ; check if the pressure reading is activated at all tstfsz lo ; is there no gas (0=off) assigned to the reading? bra calc_pres_drop_common_1 ; NO - continue bra calc_pres_drop_reset ; YES - reset everything calc_pres_drop_common_1: ; load the time accumulator into xB movff INDF1,xB+0 ; load time accumulator, low byte (had been stored) clrf xB+1 ; clear time accumulator, high byte (will be reset to 0 each round) ; get the current pressure value into divA - after copying, FSR2 will have been restored to initial address movff POSTINC2,divA+0 ; copy current pressure value to divA, low byte movff POSTDEC2,divA+1 ; copy current pressure value to divA, high byte ; check if the current pressure value is available and not outdated bsf aux_flag ; set the current pressure value as not available or outdated by default btfsc divA+1,int_not_avail_flag ; current pressure value not available? bra calc_pres_drop_common_2 ; YES - skip updating the accumulators with new data btfsc divA+1,int_outdated_flag ; current pressure outdated? bra calc_pres_drop_common_2 ; YES - skip updating the accumulators with new data bcf aux_flag ; NO to both - set current pressure value as available and up-to-date ; check if a new reading has been received movlw .2 ; capture new reading at an age of 2 (age 1 sometimes slips through...) subwf hi,W ; subtract capture-age from reading age, dump result to WREG bnz calc_pres_drop_common_2 ; result <> 0 ? YES - skip updating the accumulators ; multiply the current pressure with 16 (pre-scaling), this will also remove the flags movlw .4 ; multiply with 16 = 2^4 call mult16 ; divA = divA * 2^WREG ; get the last pressure value and store the current pressure as the new last pressure value movlw offset_FSR1_pres_last+0 ; load index of last pressure value, low byte movff PLUSW1,sub_b+0 ; copy last pressure value to sub_b, low byte movff divA+0,PLUSW1 ; store current pressure value as new last pressure value, low byte movlw offset_FSR1_pres_last+1 ; load index of last pressure value, high byte movff PLUSW1,sub_b+1 ; copy last pressure value to sub_b, high byte movff divA+1,PLUSW1 ; store current pressure value as new last pressure value, high byte ; add the last pressure value to the pressure accumulator: pres_accu (xC) += pres_last (sub_b) * 2^16 movf sub_b+0,W ; copy pres_last (sub_b) to WREG, low byte addwf xC+2,F ; add to pres_accu (xC), third byte movf sub_b+1,W ; copy pres_last (sub_b) to WREG, high byte addwfc xC+3,F ; add to pres_accu (xC), highest byte ; subtract the current pressure from the pressure accumulator: pres_accu (xC) -= pres_curr (divA) * 2^16 ; -> effectively, the pressure drop during the last measurement period has been added now bcf neg_flag ; clear neg_flag by default movf divA+0,W ; copy pres_curr (divA) to WREG, low byte subwf xC+2,F ; subtract from pres_accu (xC), third byte movf divA+1,W ; copy pres_curr (divA) to WREG, high byte subwfb xC+3,F ; subtract from pres_accu (xC), highest byte btfss STATUS,C ; did the accumulator under-run (result negative)? bsf neg_flag ; YES - memorize this ; get the current time into lo SAFE_2BYTE_COPY total_divetime_seconds,lo ; get current total dive time into lo:2 ; get the last pressure time and store the current time as the new last pressure time movlw offset_FSR1_time_last+0 ; load index of last pressure time, low byte movff PLUSW1,sub_b+0 ; copy last pressure time to sub_b, low byte movff lo+0,PLUSW1 ; store current time as new last pressure time, low byte movlw offset_FSR1_time_last+1 ; load index of last pressure time, high byte movff PLUSW1,sub_b+1 ; copy last pressure time to sub_b, high byte movff lo+1,PLUSW1 ; store current time as new last pressure time, high byte ; did the pressure accumulator under-run before because the current pressure is higher than the accumulator value was? ; we can not check & abort earlier because the current time needs to be stored along with the current pressure btfsc neg_flag ; did the pressure accumulator under-run? bra calc_pres_drop_restart ; YES - reset both accumulators and set average pressure drop to not available ; add the current time to the time accumulator: time_accu (xB) += time_curr (lo) movf lo+0,W ; copy time_curr (lo) to WREG, low byte addwf xB+0,F ; add to time_accu (xB), low byte movf lo+1,W ; copy time_curr (lo) to WREG, high byte addwfc xB+1,F ; add to time_accu (xB), high_byte ; subtract the last pressure time from time accumulator: time_accu (xB) -= time_last (sub_b) movf sub_b+0,W ; copy time_last (sub_b) to WREG, low byte subwf xB+0,F ; subtract from time_accu (xB), low byte movf sub_b+1,W ; copy time_last (sub_b) to WREG, high byte subwfb xB+1,F ; subtract from time_accu (xB), high byte btfss STATUS,C ; did the accumulator under-run (result negative) because of a wrap-around of the current time? bra calc_pres_drop_restart ; YES - reset both accumulators and set average pressure drop to not available ; check if the time accumulator (xB) is or has become too large ; this will happen if the last valid pressure reading is older than (256 - time_accu target) seconds tstfsz xB+1 ; is the time accumulator < 256 [seconds], i.e. high byte = 0 ? bra calc_pres_drop_restart ; NO - reset both accumulators and set average pressure drop to not available calc_pres_drop_common_2: ; check if the time accumulator is or has become zero to avoid a div/0 ; as long as no valid pressure value is available, the time accumulator will stay at 0 and the pressure drop calculation kept in reset movf xB+0,W ; copy time accumulator low byte to WREG, does it set the zero flag? bz calc_pres_drop_restart ; YES - reset both accumulators and set average pressure drop to not available ; duplicate pressure and time accumulators to other variables because xC and xB will get destroyed in div32x16 operation movff xC+0,lo+0 ; duplicate pres_accu to lo, lowest byte movff xC+1,lo+1 ; duplicate pres_accu to lo, second byte movff xC+2,lo+2 ; duplicate pres_accu to lo, third byte movff xC+3,lo+3 ; duplicate pres_accu to lo, highest byte movff xB+0,divA+0 ; duplicate time_accu to divA, low byte movff xB+1,divA+1 ; duplicate time_accu to divA, high byte ; calculate average pressure drop: pres_drop (xC) = pres_accu (xC) / time_accu (xB) call div32x16 ; xC = xC / xB, xC is average pressure drop in 1/(160 * 2^16) bar/sec ; is the time accumulator above target level? (only the low byte needs to be evaluated)? incf ul,W ; load the target threshold, +1 (incf) transforms cpfslt from < to <= operation cpfslt divA+0 ; is the time accumulator > target threshold ? rcall calc_pres_drop_reduce_accus ; YES - do an accumulator reduction ; do an additional half-rate (every 2nd second) accumulator reduction btfsc total_divetime_seconds+0,0 ; are we on an even second? rcall calc_pres_drop_reduce_accus ; YES - do an additional accumulator reduction ; store pressure accumulator (lo:4) - FSR0 was left pointing to address of highest byte movff lo+3,POSTDEC0 ; store pressure accumulator, highest byte movff lo+2,POSTDEC0 ; store pressure accumulator, third byte movff lo+1,POSTDEC0 ; store pressure accumulator, second byte movff lo+0,POSTDEC0 ; store pressure accumulator, lowest byte ; store the time accumulator movff divA+0,INDF1 ; store time accumulator (only the low byte will be stored) ; check if the average pressure drop for transfer to p2deco needs to be limited tstfsz xC+3 ; check if the highest byte is all zero bra calc_pres_drop_limit ; NO - limit output btfsc xC+2,7 ; check if the highest bit of the third byte is zero bra calc_pres_drop_limit ; NO - limit output ; pick and adjust the bytes from pres_drop for transfer to p2deco movff xC+1,divA+0 ; pick second byte of average pressure drop for transfer to p2deco as low byte movff xC+2,divA+1 ; pick third byte of average pressure drop for transfer to p2deco as high byte movlw .3 ; divide by 8 = 2^3 call div16 ; divA = divA / 2^WREG bra calc_pres_drop_common_3 calc_pres_drop_limit: ; limit output to 0x0FFF movlw LOW 0x0FFF ; set output to 0x0FFF movwf divA+0 ; ... movlw HIGH 0x0FFF ; ... movwf divA+1 ; ... bsf divA+1,int_warning_flag ; set warning flag indicating out-of-range calc_pres_drop_common_3: ; set the average pressure drop as not available if the last pressure reading is outdated or not available btfsc aux_flag ; is the last pressure reading outdated or not available? bsf divA+1,int_not_avail_flag ; YES - set pressure drop to not available, too ; set the average pressure drop as outdated if time_accu (divA) < (target threshold / 2) rrncf ul,W ; load time accumulator target value / 2 into WREG decf WREG,W ; subtract 1 to transform cpfsgt from > to >= operation cpfsgt INDF1 ; time accumulator < (target threshold / 2) ? bsf divA+1,int_outdated_flag ; YES - set outdated flag ; write average pressure drop to p2deco interface movlw offset_FSR2_press_drop+0 ; load index of average pressure drop, low byte movff divA+0,PLUSW2 ; store average pressure drop, low byte movlw offset_FSR2_press_drop+1 ; load index of average pressure drop, high byte movff divA+1,PLUSW2 ; store average pressure drop, high byte ; done return calc_pres_drop_reduce_accus: ; subtract 1 second from the time accumulator: time_accu (divA) -= 1 (only the low byte needs to be processed) decf divA+0,F ; decrement low byte of time_accu ; subtract average pressure drop per second from pressure accumulator: press_accu (lo) -= press_drop (xC) movf xC+0,W ; copy press_drop(xC) to WREG, lowest byte subwf lo+0,F ; subtract from pres_accu, lowest byte movf xC+1,W ; copy press_drop(xC) to WREG, second byte subwfb lo+1,F ; subtract from pres_accu, second byte movf xC+2,W ; copy press_drop(xC) to WREG, third byte subwfb lo+2,F ; subtract from pres_accu, third byte movf xC+3,W ; copy press_drop(xC) to WREG, highest byte subwfb lo+3,F ; subtract from pres_accu, highest byte btfsc STATUS,C ; did the buffer under-run (result negative)? return ; NO - done clrf lo+0 ; YES - clear pressure accumulator, lowest byte clrf lo+1 ; - clear pressure accumulator, second byte clrf lo+2 ; - clear pressure accumulator, third byte clrf lo+3 ; - clear pressure accumulator, highest byte return ; - done calc_pres_drop_reset: ; store the current gas as the last gas movlw offset_FSR1_gas__last ; load index of last gas movff lo,PLUSW1 ; store current gas as new last gas ; clear last pressure value movlw offset_FSR1_pres_last+0 ; load index of last pressure value, low byte clrf PLUSW1 ; clear last pressure value, low byte movlw offset_FSR1_pres_last+1 ; load index of last pressure value, high byte clrf PLUSW1 ; clear last pressure value, high byte ; clear last pressure time movlw offset_FSR1_time_last+0 ; load index of last pressure time, low byte clrf PLUSW1 ; clear last pressure time, low byte movlw offset_FSR1_time_last+1 ; load index of last pressure time, high byte clrf PLUSW1 ; clear last pressure time, high byte calc_pres_drop_restart: ; clear pressure accumulator - FSR0 was left pointing to address of highest byte clrf POSTDEC0 ; clear pressure accumulator, highest byte clrf POSTDEC0 ; clear pressure accumulator, third byte clrf POSTDEC0 ; clear pressure accumulator, second byte clrf POSTDEC0 ; clear pressure accumulator, lowest byte ; clear time accumulator clrf INDF1 ; clear time accumulator ; clear pressure drop and set it to not available movlw offset_FSR2_press_drop+0 ; load index of average pressure drop, low byte clrf PLUSW2 ; clear average pressure drop, low byte movlw offset_FSR2_press_drop+1 ; load index of average pressure drop, high byte clrf PLUSW2 ; clear average pressure drop, high byte bsf PLUSW2,int_not_avail_flag ; set flag for data not available return ; done ;============================================================================= ; set up SAC calculation dependent on TR mode ; global configure_sac_calculation configure_sac_calculation: movlw time_accu_target_OC ; load time accumulator target value for OC as default movwf ul ; store it in ul movff opt_TR_mode,WREG ; get TR mode dcfsnz WREG,W ; TR mode = 1 (on)? bra configure_sac_calculation_1 ; YES dcfsnz WREG,W ; TR mode = 2 (ind.double)? bra configure_sac_calculation_2 ; YES dcfsnz WREG,W ; TR mode = 3 (CCR Dil+O2)? bra configure_sac_calculation_3 ; YES bra configure_sac_calculation_4 ; NO to all - was disabled then (or invalid) configure_sac_calculation_1: ; TR mode 1: calculate SAC on 1st reading rcall calc_pres_drop_1st ; calculate pressure drop on 1st reading movlw .1 ; select SAC mode 1: SAC on 1st reading bra configure_sac_calculation_5 ; goto exit configure_sac_calculation_2: ; TR mode 2: independent double rcall calc_pres_drop_1st ; calculate pressure drop on 1st reading rcall calc_pres_drop_2nd ; calculate pressure drop on 2nd reading movlw .3 ; select SAC mode 3: SAC on higher of both readings bra configure_sac_calculation_5 ; goto exit configure_sac_calculation_3: ; TR mode 3: CCR Dil+O2 btfsc FLAG_bailout_mode ; in bailout? bra configure_sac_calculation_1 ; YES - handle alike TR mode 1 movlw time_accu_target_CCR ; load time accumulator target value for CCR mode movwf ul ; store it in ul rcall calc_pres_drop_2nd ; calculate pressure drop on 2nd reading movlw .4 ; select SAC mode 4: SAC on 2nd reading, O2 usage bra configure_sac_calculation_5 ; goto exit configure_sac_calculation_4: clrf WREG ; select SAC mode 0 (disabled) configure_sac_calculation_5: movff WREG,char_I_SAC_mode ; write SAC mode selection return ;============================================================================= ENDIF END