;------------------------------------------------------------------- ; PROGRAM NAME & REVISION INFORMATION ; ;------------------------------------------------------------------- ; WHEELCHAIR SPEED CONTROLLER ; ; VERSION 5.0 ; ; DESIGNED BY E BROUWER ; ; DATE: NOVEMBER 2016 ;------------------------------------------------------------------- ; DESCRIPTION ; ; PREVENTS INCORRECT SELECTION OF FORWARD/REVERSE ; WILL BLOCK H-BRIDGE IF INPUTS ARE INVALID ; ; TEMPERATURE MEASURED USING LM35 ; COOLING FAN CONTROLLED BY TEMPERATURE ; H-BRIDGE WILL SWITCH OFF IF TEMPERATURE EXCEED LIMIT ; ;------------------------------------------------------------------- ; PIN ASSIGNMENTS ; ;------------------------------------------------------------------- ; PIN INPUT/OUTPUT USED FOR ; GP0 OUTPUT FWD_OUT ; GP1 OUTPUT REV_OUT ; GP2 OUTPUT FAN_OUT ; GP3 INPUT REV_IN ; GP4 INPUT TEMP_IN ; GP5 INPUT FWD_IN ; ;------------------------------------------------------------------- ; COMPILER SETTINGS ; ;------------------------------------------------------------------- LIST F=INHX8M, P=12F675, R=HEX #include ;CONFIGRATION BITS ;----------------- __CONFIG _CPD_OFF & _CP_ON & _BODEN_OFF & _MCLRE_OFF & _PWRTE_ON & _WDT_ON & _INTRC_OSC_NOCLKOUT ;------------------------------------------------------------------- ; VARIABLES/LABELS DECLARATIONS ; ;------------------------------------------------------------------- CBLOCK H'20' ;DEFINE RAM LOCATION LM35L ;LM35 TEMPERATURE LOW BYTE LM35H ;LM35 TEMPERATURE HIGH BYYR FLAGS ;FLAGS DLY ;DELAY COUNTER TEMP ;TEMP ENDC ;DEFINE TEMPERATURE SETTINGS ;--------------------------- #DEFINE FAN_OFF .80 ;40 DEGREES C #DEFINE FAN_ON .102 ;50 DEGREES C #DEFINE TEMP_RST .81 ;40 DEGREES C #DEFINE TEMP_TRIP .163 ;80 DEGREES C ;DEFINE I/O PINS ;--------------- #DEFINE FWD_IN GPIO,5 ; #DEFINE REV_IN GPIO,3 ; #DEFINE TEMP_IN GPIO,4 ; #DEFINE FWD_OUT GPIO,0 ; #DEFINE REV_OUT GPIO,1 ; #DEFINE FAN_OUT GPIO,2 ; ;DEFIEN FLAGS ;------------ #DEFINE IN_FWD FLAGS,0 ;COPY OF FWD INPUT #DEFINE IN_REV FLAGS,1 ;COPY OF REV INPUT #DEFINE FWD_FLAG FLAGS,2 ;FORWARD COMMAND #DEFINE REV_FLAG FLAGS,3 ;REVERSE COMMAND #DEFINE FWD_OLD FLAGS,4 ;PREVIOUS FORWARD COMMAND #DEFINE REV_OLD FLAGS,5 ;PREVIOUS REVERSE COMMAND #DEFINE ESC_OFF FLAGS,6 ;ESC OVER-TEMPERATURE FLAG ;------------------------------------------------------------------- ; START-UP OF PIC ; ;------------------------------------------------------------------- ORG 0 ;RESET VECTOR GOTO START ; / ORG 4 ;INTERRUPT VECTOR GOTO ISR ; / ;------------------------------------------------------------------- ; SET-UP OF REGISTERS AND INTERRUPTS ; ;------------------------------------------------------------------- START CALL H'3FF' ;LOAD CALIBRATION DATA BSF STATUS,RP0 ;SET BANK 1 MOVWF OSCCAL ;SET CALIRATION BCF STATUS,RP0 ;SET BANK 0 ;REMOVE BELOW - USED FOR CODE TESTING ;------------------------------------ ;------------------------------------ ;REMOVE ABOVE - USED FOR CODE TESTING ;------------------------------------ ;SETUP OF REGISTERS ;------------------ CLRF GPIO ;CLEAR PORTS CLRF FLAGS ;CLEAR FLAGS MOVLW B'111' ;SET COMPARATOR TO OFF MOVWF CMCON ; / BSF STATUS,RP0 ;SET BANK 1 MOVLW B'01101000' ;SETUP A/D PINS MOVWF ANSEL MOVLW B'000000' ;ENABLE WEAK PULL-UPS MOVWF WPU ; / MOVLW B'111000' ;SETUP IO DIRECTION MOVWF TRISIO ; / MOVLW B'10001111' ;B'00101010'LOAD OPTION REGISTER ;BIT 7 - 0 = WEAK PULL-UPS ENABLED ;BIT 6 - 0 = INTERRUPT ON RISING EDGE OF GP2 ;BIT 5 - 1 = TMR0 CLOCK SET TO GP2 PIN ;BIT 4 - 1 = TMR0 INC ON HIGH TO LOW ;BIT 3 - 1 = PRESCALER ASSIGNED TO WDT ;BIT 2..1 = PRESCALER SET TO 1:256 MOVWF OPTION_REG ; / BCF STATUS,RP0 ;SET BANK 0 ;READ A/D CONVERTER ;------------------ CALL READ_A2D ;POWER ON DELAY ;-------------- ; BSF FAN_OUT CALL DLY_500 ;WAIT FOR SIGNALS TO STABALISE CALL DLY_500 ;WAIT FOR SIGNALS TO STABALISE ; BCF FAN_OUT ;------------------------------------------------------------------------ ;` MAIN PROGRAAM LOOP ; ;------------------------------------------------------------------------ WAIT CLRWDT ;RESET WATCHDOG TIMER ;READ A/D CONVERTER ;------------------ CALL READ_A2D ;READ FORWARD/REVERSE INPUTS ;--------------------------- BTFSS FWD_IN ;IS FWD_IN LOW? BCF IN_FWD ;YES, CLEAR IN_FWD ; BCF FWD_OUT ;YES, CLEAR IN_FWD BTFSC FWD_IN ;IS FWD_IN HIGH? BSF IN_FWD ;YES, SET IN_FWD ; BSF FWD_OUT ;YES, SET IN_FWD BTFSS REV_IN ;IS REV_IN LOW? BCF IN_REV ;YES, CLEAR IN_REV ; BCF REV_OUT ;YES, CLEAR IN_REV BTFSC REV_IN ;IS REV_IN HIGH? BSF IN_REV ;YES, SET IN_REV ; BSF REV_OUT ;YES, SET IN_REV ; GOTO WAIT ;PREVENT SWITCHING BETWEEN FORWARD/REVERSE WITHOUT FIRST STOP ;------------------------------------------------------------ ;CHECK IF FWD = 0 AND REV = 0 ;---------------------------- BTFSC IN_FWD ;IS FWD LOW? GOTO CHK01 ;NO BTFSC IN_REV ;IS REV LOW? GOTO CHK01 ;NO ;HERE, FWD = 0 AND REV = 0 ;------------------------- BCF FWD_FLAG ;SET STATUS FLAG BCF REV_FLAG ;SET STATUS FLAG BCF FWD_OLD BCF REV_OLD ;CHECK IF FWD = 1 AND REV = 0 ;---------------------------- CHK01 BTFSS IN_FWD ;IS FWD HIGH? GOTO CHK02 ;NO BTFSC IN_REV ;IS REV LOW? / GOTO CHK02 ;NO ;HERE, FWD = 1 AND REV = 0 ;WAS PREVIOUS STATE REVERSE? ;--------------------------- BTFSC REV_OLD ;PREVIOUS STATE REVERSE? GOTO CHK02 ;YES ;SAFE TO SELECT FORWARD ;---------------------- BSF FWD_FLAG ;SET STATUS FLAG BCF REV_FLAG ;SET STATUS FLAG ;CHECK IF FWD = 0 AND REV = 1 ;---------------------------- CHK02 BTFSC IN_FWD ;IS FWD LOW? GOTO CHK03 ;NO BTFSS IN_REV ;IS REV HIGH? GOTO CHK03 ;NO ;HERE, FWD = 0 AND REV = 1 ;------------------------- ;WAS PREVIOUS STATE FORWARD? ;--------------------------- BTFSC FWD_OLD ;PREVIOUS STATE FORWARD? GOTO CHK03 ;YES ;SAFE TO SELECT REVERSE ;---------------------- BCF FWD_FLAG ;SET STATUS FLAG BSF REV_FLAG ;SET STATUS FLAG BSF FWD_OLD BSF REV_OLD ;CHECK IF FWD = 1 AND REV = 1 ;---------------------------- CHK03 BTFSS IN_FWD ;IS FWD HIGH? GOTO CHK04 ;NO BTFSS IN_REV ;IS REV HIGH? GOTO CHK04 ;NO ;HERE, FWD = 1 AND REV = 1 ;------------------------- BCF FWD_FLAG ;SET STATUS FLAG BCF REV_FLAG ;SET STATUS FLAG ;CHECK TEMERATURE ;IF < 40C, FAN OFF ;--------------------------------- CHK04 MOVLW FAN_OFF SUBWF LM35L,0 BTFSC STATUS,C GOTO CHK05 BCF FAN_OUT ;TURN OFF FAN ;CHECK TEMERATURE ;IF > 50C, FAN ON ;--------------------------------- CHK05 MOVF LM35L,0 SUBLW FAN_ON BTFSC STATUS,C GOTO CHK06 BSF FAN_OUT ;TURN ON FAN ;CHECK TEMERATURE ;IF < 50C, ESC ON ;--------------------------------- CHK06 MOVLW TEMP_RST SUBWF LM35L,0 BTFSC STATUS,C GOTO CHK07 BCF ESC_OFF ;ENABLE ECS ;CHECK TEMERATURE ;IF > 80C, ESC OFF ;--------------------------------- CHK07 MOVF LM35L,0 SUBLW TEMP_TRIP BTFSC STATUS,C GOTO CHK08 BSF ESC_OFF ;TURN OFF ESC BSF FWD_OLD BSF REV_OLD ;SET FORWARD/REVERSE OUTPUTS ;--------------------------- ;DISABLE FORWARD/REVERSE OUTPUTS IF TEMPERATURE > 80C (ESC_OFF FLAG SET) ;------------------------------------------------------------------------ CHK08 BTFSS ESC_OFF ;IS TEMP > 80C? GOTO CHK09 ;NO ;OVER TEMPERATURE CONDITION. DISABLE H-BRIDGE BY TURNING OFF ;FWD AND REV OUTPUTS ;------------------------------------------------------------ BCF FWD_FLAG ;DISABLE FORWARD BCF REV_FLAG ;DISWABLE REVERSE BCF FWD_OUT ;FWD_OUT OFF BCF REV_OUT ;REV_OUT OFF GOTO DONE ;DONE ;IF TEMPERATURE OK, SWITCH FORWARD/REVERSE SIGNALS AS PER INPUTS ;--------------------------------------------------------------- CHK09 BTFSS FWD_FLAG ;FORWARD SELECTED? GOTO CHK10 ;NO BTFSC REV_FLAG ;REVERSE NOT SELECTED? GOTO CHK10 ;NO ;TURN ON FORWARD OUTPUT ;---------------------- BCF REV_OUT ;YES, ENABLE FORWARD BSF FWD_OUT ; / BSF FWD_OLD ; / GOTO DONE ;DONE CHK10 BTFSS REV_FLAG ;REVERSE SELECTED? GOTO CHK11 ;NO BTFSC FWD_FLAG ;FORWARD NOT SELECTED? GOTO CHK11 ;NO ;TURN ON REVERSE OUTPUT ;----------------------- BCF FWD_OUT ;YES, ENABLE REVERSE BSF REV_OUT ; / BSF REV_OLD ; / GOTO DONE ;DONE ;INVALID SELECTION, TURN OFF OUTPUTS ;----------------------------------- CHK11 BCF FWD_OUT ;DISABLE FORWARD/REVERSE BCF REV_OUT ; / ;END OF MAIN LOOP - REPEAT ;------------------------- DONE CALL DELAY ;SMALL DELAY GOTO WAIT ;------------------------------------------------------------------------ ;` READ A/D CONVERTER ; USE BITS 7..0 ;------------------------------------------------------------------------ READ_A2D MOVLW B'10001101' MOVWF ADCON0 ;SET CHANNEL 1 CLRF TMR0 BTFSS TMR0,5 ;WAIT REQUIRED ACQUISITION TIME GOTO $-1 ; / BSF ADCON0,GO ;START CONVERSION BTFSC ADCON0,GO ;WAIT FOR A/D CONVERSION GOTO $-1 MOVF ADRESH,0 ;READ A/D HI RESULT MOVWF LM35H ;SAVE IN FILE BSF STATUS,RP0 ;BANK1 MOVF ADRESL,0 ;READ A/D LO RESULT MOVWF LM35L ;SAVE IN FILE BCF STATUS,RP0 ;BANK0 ;IF LM35H <> 0, SET LM35L TO 255 ;------------------------------- MOVF LM35H,0 BTFSC STATUS,Z RETURN MOVLW .255 MOVWF LM35L RETURN ;------------------------------------------------------------------------ ; INTERRUPT SERVICE ROUTINE ; ;------------------------------------------------------------------------ ISR RETFIE ;RETURN & RESET INTERRUPTS ;------------------------------------------------------------------------ ; 750us DELAY ; ;------------------------------------------------------------------------ DELAY MOVLW D'106' ;LOAD DELAY VARIABLE MOVWF DLY ; / DLY_1 NOP NOP NOP NOP DECFSZ DLY,1 ;DECREASE DLY, SKIP IF ZERO GOTO DLY_1 ;NOT ZERO,WAIT NOP NOP NOP NOP RETURN ;RETURN ;------------------------------------------------------------------------ ; 0.5s DELAY ; ;------------------------------------------------------------------------ DLY_500 MOVLW D'65' ;REPEAT TEMP TIMES MOVWF TEMP ; / DLY_51 CALL DELAY ;750us DELAY CALL DELAY ;750us DELAY CALL DELAY ;750us DELAY CALL DELAY ;750us DELAY CALL DELAY ;750us DELAY CALL DELAY ;750us DELAY CALL DELAY ;750us DELAY CALL DELAY ;750us DELAY CALL DELAY ;750us DELAY CALL DELAY ;750us DELAY CALL DELAY ;750us DELAY DECFSZ TEMP,1 ; / GOTO DLY_51 RETURN ;------------------------------------------------------------------------ ; END OF PROGRAM ; ;------------------------------------------------------------------------ END