;******************************************************** ; ; This is a program to run the PIC 16F877 or 16C77 ; MPU to drive the Ultra Sonic board that was built ; for the 2000 Aerial Robotics Team. ; Port B will be used for the 6500 module drive, and the CCP1 ; pin for both echo signals. Below is the pin out ; ; PORTB... ; 0=INIT 1 ; 1=BINH 1 ; 2=BLNK 1 ; 3=N/A ; 4=INIT 2 ; 5=BINH 2 ; 6=BLNK 2 ; 7=N/A ; ; CCP1=ECHO 1 and ECHO 2 ; ;*********************************************************** ;***** Program Hiarchie ********************* ; ; Initialization ; Polling Routine ; run mod 1 ; delay ; transmit data of mod 1 ; run mod 2 ; delay ; transmit data of mod 2 ; IntService ; ECHO_RX ; BINH running ; ;******************************************** list P=PIC16C77, F=INHX8M, C=160, N=77, ST=OFF, MM=OFF, R=DEC, X=OFF #include P16C77.inc ; this is the standard header file for 16c77 list list __config(_CP_OFF & _PWRTE_ON & _XT_OSC & _WDT_OFF & _BODEN_OFF) ;***** Equates ****************************** Bank0Ram equ H'20' MaxCount equ 50 ;***** Variables *************************** cblock Bank0Ram MACRO_TEMP TEMP TIME1 ;this is the low byte for the CCP1L TIME2 ;this is the high byte for the CCP1H W_TEMP ;temp used in IntService STATUS_TEMP ;temp used in IntService FSR_TEMP ;temp used in IntService MASK ;used to set the right bit in PORTB Nibble1 Nibble2 Nibble3 Nibble4 endc ;***** Macro Definitions ******************* MOVLF macro literal,dest movlw literal movwf dest endm MOVFF macro source,dest movf source,W movwf dest endm DELAY macro time local Again movlw time movwf MACRO_TEMP Again decfsz MACRO_TEMP goto Again endm ;***** Vectors ********************************* org H'000' ;reset vectors goto MainLine ;Branch past tables org H'004' ;Interupt vector goto IntService ;Branch to interupt service routine ;***** Tables ******************************************** ;***** End of Table ************************************** ;***** MainLine code ************************************* MainLine call Initial ;initialize everything MainLoop call FIRE_1 ;fire the module 1 MOVLF 7,TEMP Delay1 call LoopTime ;to wait 0.5 sec decfsz TEMP,F ;dec the counter goto Delay1 call CONVERT ;convert TIME1 and TIME2 to HEX ascii call TRANSMIT ;transmit the data in Nibble1 - Nibble3 call FIRE_2 ;fire module 2 MOVLF 7,TEMP Delay2 call LoopTime ;to wait 0.5 sec decfsz TEMP,F ;dec the counter goto Delay2 call CONVERT ;convert the data into ascii call TRANSMIT ;transmit the data in TIME1 and TIME2 goto MainLoop ;***** Initial Sub *********************************** ; ; this will initialize all of the ports and etc. Initial bsf STATUS,RP0 ;set to Bank 1 MOVLF B'00000111',ADCON1 ;setting all AD pins to digital I/O clrf TRISA ;setting all port a to output clrf TRISB ;setting PORTB as out MOVLF B'00000100',TRISC ;all port c output, CCP1 in MOVLF B'11110000',TRISD ;all input for port d clrf TRISE ;all output for port e MOVLF 249,PR2 ;setting LoopTime time MOVLF B'00000100',PIE1 ;enable CCP1 interupt MOVLF B'00000001',PIE2 ;enable CCP2 interupt MOVLF B'00100100',TXSTA ;setting the serial port info MOVLF 25,SPBRG ;setting baud rate generator to 9600 bcf STATUS,RP0 ;setting to bank 0 ram MOVLF B'01001101',T2CON ;setting up timer 2 for looptie MOVLF B'00000000',T1CON ;setting up timer 1, MOVLF B'00000101',CCP1CON ;capture on rising edge MOVLF B'00001010',CCP2CON ;compare for CCP2, generate interupt clrf PORTA clrf PORTB clrf PORTC clrf PORTD clrf PORTE MOVLF B'10000000',RCSTA ;enable the serial port MOVLF B'11000000',INTCON ;enable interupts return ;***** FIRE_1 subroutine ***************************** ; ; this is used to set up and fire module 1 FIRE_1 MOVLF H'E8',CCPR2L ;use CCP2 for BINH (Low 1ms) MOVLF H'03',CCPR2H ;the high byte clrf TMR1L ;clear the timer 1 low byte clrf TMR1H ;clear the timer 1 high byte clrf CCPR1L ;clear the record byte clrf CCPR1H ;clear the high byte clrf PORTB ;ready PORTB MOVLF B'00000010',MASK ;used to xor into PORTB in INT sub bsf PORTB,0 ;set INIT 1 bsf T1CON,0 ;start TIMER 1 MOVLF PIE1,FSR ;indirect addressing bcf INDF,2 ;disable CCP1 interupt call T40 ;delay for 40 us MOVLF PIE1,FSR ;indirect addressing bsf INDF,2 ;reset interupts ; bcf PIR1,2 ;make sure the CCP1IF is clear ;ECHO1_LOOKING ; btfss PIR1,2 ;testing CCP1IF ; goto ECHO1_LOOKING ; bcf T1CON,0 ;stop the timer ; MOVFF CCPR1L,TIME1 ;save the low time ; MOVFF CCPR1H,TIME2 ;save the high time ; call LoopTime ;delay for 10 ms ; clrf PORTB ;clear all PORTB return ;***** FIRE_2 subroutine ***************************** ; ; this is used to set up and fire module 2 FIRE_2 MOVLF H'E8',CCPR2L ;use CCP2 for BINH (Low 1ms) MOVLF H'03',CCPR2H ;the high byte clrf TMR1L ;clear the timer 1 low byte clrf TMR1H ;clear the timer 1 high byte clrf CCPR1L ;clear the record byte clrf CCPR1H ;clear the high byte clrf PORTB ;ready PORTB MOVLF B'00100000',MASK ;used to xor into PORTB in INT sub bsf PORTB,4 ;set INIT 2 bsf T1CON,0 ;start TIMER 1 MOVLF PIE1,FSR ;indirect addressing bcf INDF,2 ;disable interupt call T40 ;delay for 40 us MOVLF PIE1,FSR ;indirect addressing bsf INDF,2 ;reset interupts ; bcf PIR1,2 ;make sure CCP1IF is clear ;ECHO2_LOOKING ; btfss PIR1,2 ;testing CCP1IF ; goto ECHO2_LOOKING ; bcf T1CON,0 ;stop the timer ; MOVFF CCPR1L,TIME1 ;save the low time ; MOVFF CCPR1H,TIME2 ;save the high time ; call LoopTime ;delay for 10 ms ; clrf PORTB ;clear all PORTB return ;***** TRANSMIT subroutine *************************** ; ; this is used to send the data that is stored in ; TIME1 (low byte) and TIME2 (high byte) out the ; serial port. TRANSMIT btfss PIR1,4 ;testing to see if TXREG is clear goto TRANSMIT ;if not keep looking MOVFF Nibble4,TXREG ;send the first nibble CHECKING1 btfss PIR1,4 ;test to see if done goto CHECKING1 ;if not MOVFF Nibble3,TXREG ;send the second nibble CHECKING2 btfss PIR1,4 ;test to see if done goto CHECKING2 ;if not MOVFF Nibble3,TXREG CHECKING25 btfss PIR1,4 goto CHECKING25 MOVFF Nibble2,TXREG ;send the third nibble CHECKING3 btfss PIR1,4 ;test to see if done goto CHECKING3 MOVFF Nibble2,TXREG CHECKING35 btfss PIR1,4 goto CHECKING35 MOVFF Nibble1,TXREG ;send the last nibble CHECKING4 btfss PIR1,4 ;test to see if done goto CHECKING4 MOVFF Nibble1,TXREG CHECKING45 btfss PIR1,4 goto CHECKING45 MOVLF H'0D',TXREG ;send a space CHECKING5 btfss PIR1,4 ;testing to see if done goto CHECKING5 MOVLF H'0D',TXREG ;carrage return CHECKING55 btfss PIR1,4 goto CHECKING55 MOVLF H'0A',TXREG ;new line CHECKING6 btfss PIR1,4 goto CHECKING6 MOVLF H'0A',TXREG ;new line CHECKING65 btfss PIR1,4 goto CHECKING65 return ;***** CONVERT subroutine ****************************** ; ; this will convert the data in TIME1 (low byte) ; and TIME2 (high byte) into ascii code for ; Nibble1, Nibble2, Nibble3. CONVERT MOVFF TIME1,TEMP ;coping low time byte to temp movlw B'00001111' andwf TEMP,F movlw 10 subwf TEMP,W ;TEMP-W=W btfss STATUS,C ;test the carry bit goto NUMBER_CASE ; for letter case decf TEMP,W andlw B'00000111' ;keep that last 3 bits addlw B'01000000' ;adding in the high set goto FirstDone NUMBER_CASE movf TEMP,W addlw B'00110000' FirstDone movwf Nibble1 ;copy the value to Nibble1 MOVFF TIME1,TEMP swapf TEMP,F ;time for the next nibble movlw B'00001111' andwf TEMP,F movlw 10 subwf TEMP,W btfss STATUS,C goto NextNumber decf TEMP,W andlw B'00000111' addlw B'01000000' goto SecondDone NextNumber movf TEMP,W addlw B'00110000' SecondDone movwf Nibble2 MOVFF TIME2,TEMP ;coping low time byte to temp movlw B'00001111' andwf TEMP,F movlw 10 subwf TEMP,W ;W-TEMP=W btfss STATUS,C ;test the carry bit goto LastNumber ; for letter case decf TEMP,W andlw B'00000111' ;keep that last 3 bits addlw B'01000000' ;adding in the high set goto ThirdDone LastNumber movf TEMP,W addlw B'00110000' ThirdDone movwf Nibble3 ;copy the value to Nibble3 swapf TIME2,W ;coping low time byte to temp movwf TEMP movlw B'00001111' andwf TEMP,F movlw 10 subwf TEMP,W ;W-TEMP=W btfss STATUS,C ;test the carry bit goto VeryLastNumber ; for letter case decf TEMP,W andlw B'00000111' ;keep that last 3 bits addlw B'01000000' ;adding in the high set goto ForthDone VeryLastNumber movf TEMP,W addlw B'00110000' ForthDone movwf Nibble4 ;copy the value to Nibble4 return ;***** LoopTime subroutine *************************** ; ; this will use timer2 to complete counting 10 mS LoopTime btfss PIR1,TMR2IF ;check to see if time is up goto LoopTime bcf PIR1,TMR2IF ;reset for next time return ;***** T40 subroutine **************************** ; ; this will use up 40 us of time to ignore the ; noise on the echo line from the fireing. T40 MOVLF 40,TEMP ;a counter HERE decfsz TEMP,F ;dec the counter goto HERE return ;***** Interupt service ************************** ; ; this is an interupt service IntService movwf W_TEMP ;saving W swapf STATUS,W ;saving STATUS movwf STATUS_TEMP Poll btfsc PIR1,CCP1IF ;testing to see if ECHO is here goto ECHO_RX btfsc PIR2,CCP2IF ;testing to see if compare is doen goto SET_BINH swapf STATUS_TEMP,W ;restore status movwf STATUS swapf W_TEMP,F ;restore W swapf W_TEMP,W retfie ;***** ECHO_RX subroutine ************************* ; ; this is used to caputure the time when a echo is recieved. ECHO_RX bcf PIR1,CCP1IF ;clear the flag bcf T1CON,0 ;stop the timer MOVFF CCPR1L,TIME1 ;save the low time MOVFF CCPR1H,TIME2 ;save the high time call LoopTime ;delay for 10 ms clrf PORTB ;clear all PORTB goto Poll ;***** SET_BINH subroutine ************************ ; ; this is used to set the bit masked in MASK to PORTB ; basically to set the BINH SET_BINH bcf PIR2,CCP2IF ;clear the flag movf MASK,W ;move mask to W xorwf PORTB,F ;xor W into PORTB itself goto Poll ;***** End of all programs *********************** end