; developed on PICkit2 44pin demo board with 16F887 ; 16F887 demo board wiring #ifdef __16F887 #include __CONFIG _CONFIG1, _LVP_OFF & _FCMEN_OFF & _IESO_OFF & _BOR_OFF & _CPD_OFF & _CP_OFF & _MCLRE_OFF & _PWRTE_ON & _WDT_OFF & _INTRC_OSC_NOCLKOUT __CONFIG _CONFIG2, _WRT_OFF & _BOR21V #define USER_RAM 0x20 #define SHARED_RAM 0x70 #define Output PORTD #define OUTBIT PORTD,7 #define Input PORTB #define INPBIT PORTB,0 #define Display PORTD initports MACRO banksel ANSEL movlw 0xFF movwf ANSEL banksel ANSELH movlw 0x00 movwf ANSELH banksel TRISA movlw 0xFF movwf TRISA movlw 0x01 movwf TRISB clrf TRISD ENDM inittmr0 MACRO banksel OPTION_REG movlw B'10001000' ; PS on WDT, min prescale (/1) movwf OPTION_REG ENDM initirq MACRO banksel INTCON movlw B'10100000' ; enable Timer 0 and global interrupts movwf INTCON ENDM #endif ; 12F675 board wiring #ifdef __12F675 #include __CONFIG _BODEN_OFF & _CPD_OFF & _CP_OFF & _MCLRE_OFF & _PWRTE_ON & _WDT_OFF & _INTRC_OSC_NOCLKOUT #define USER_RAM 0x20 #define SHARED_RAM 0x50 #define Output GPIO #define OUTBIT GPIO,2 #define Input GPIO #define INPBIT GPIO,4 #define Display 0x5f initports MACRO banksel ANSEL movlw 0x00 movwf ANSEL banksel CMCON MOVLW 07h MOVWF CMCON banksel TRISIO MOVLW B'00010000' MOVWF TRISIO banksel WPU movlw 0xFF movwf WPU ENDM inittmr0 MACRO banksel OPTION_REG movlw B'00001000' ; PS on WDT, min prescale (/1), pullups movwf OPTION_REG ENDM initirq MACRO banksel INTCON movlw B'10100000' ; enable Timer 0 and global interrupts movwf INTCON ENDM #endif #define PWMC_MASK B'00011111' #define PWMD_MASK B'00011111' ; keyboard timings #define TIM D'50' #define FIRST D'25' #define REST D'6' cblock USER_RAM Delay1 ; Assign an address to label Delay1 Delay2 T0Semaphore tcnt pwmc pwmd kbd okbd kbdcnt bitvars endc #define KBD_SHORT bitvars,0 ; signal for short keypress #define PWM_DIR bitvars,1 ; pwm modifying direction #define PWM_EN bitvars,2 ; pwm output enable (on/off function) ; Flag Definitions cblock SHARED_RAM ; put these up in unbanked RAM W_Save STATUS_Save endc org 0 goto Start org 4 ISR: movwf W_Save movf STATUS,w movwf STATUS_Save banksel INTCON btfsc INTCON,T0IF goto ServiceTimer0 goto ExitISR ServiceTimer0: bcf INTCON,T0IF banksel pwmd movf pwmd,w banksel Display movwf Display banksel bitvars btfsc PWM_EN goto dopwm banksel Output bcf OUTBIT goto key dopwm banksel pwmc incf pwmc,w andlw PWMC_MASK movwf pwmc subwf pwmd,w btfss STATUS,C goto noc banksel Output bsf OUTBIT goto key noc banksel Output bcf OUTBIT key banksel tcnt decfsz tcnt,f goto kbdend movlw TIM movwf tcnt clrw banksel Input btfss INPBIT addlw 1 banksel kbd movwf kbd xorwf okbd,w btfsc STATUS,Z goto up_or_down ; key is just pressed or released movf kbd,f btfss STATUS,Z goto pressed ; key is just released banksel bitvars btfsc KBD_SHORT goto short ; long keypress is just released ; toggle pwm modify direction banksel bitvars btfsc PWM_DIR goto pwmdir1 bsf PWM_DIR goto kbdend pwmdir1 bcf PWM_DIR goto kbdend short ; short keypress is just released ; toggle pwm enable bit banksel bitvars btfsc PWM_EN goto pwmen1 bsf PWM_EN goto kbdend pwmen1 bcf PWM_EN goto kbdend pressed ; key is just pressed banksel bitvars bsf KBD_SHORT banksel kbdcnt movlw FIRST movwf kbdcnt goto kbdend ; key is in up or down state up_or_down banksel kbd movf kbd,f btfss STATUS,Z goto down ; key is in up state goto kbdend down ; key is in down state decf kbdcnt,f btfss STATUS,Z goto kbdend ; long press banksel bitvars bcf KBD_SHORT bsf PWM_EN movlw REST movwf kbdcnt movf pwmd,w btfss PWM_DIR xorlw PWMD_MASK btfsc STATUS,Z goto kbdend movlw 1 btfsc PWM_DIR movlw -1 addwf pwmd,w andlw PWMD_MASK movwf pwmd goto kbdend kbdend banksel kbd movf kbd,w movwf okbd ExitISR: movf STATUS_Save,w movwf STATUS swapf W_Save,f swapf W_Save,w retfie ; main program Start: banksel pwmc clrf pwmc clrf tcnt movlw 0 ; movlw PWMD_MASK movwf pwmd banksel kbd clrf kbd clrf okbd banksel bitvars bcf KBD_SHORT bcf PWM_DIR ; bsf PWM_DIR bcf PWM_EN initports ; banksel Output ; bsf OUTBIT ;sss ; goto sss inittmr0 movlw 0xFF banksel Display movwf Display initirq MainLoop: goto MainLoop ; Delay Subroutine. Enter delays Wreg * 771uS + 5 uS including call and return Delay: movwf Delay2 ; DelayLoop: decfsz Delay1,f ; Waste time. goto DelayLoop ; The Inner loop takes 3 instructions per loop * 256 loopss = 768 instructions decfsz Delay2,f ; The outer loop takes and additional 3 instructions per lap * 256 loops goto DelayLoop ; (768+3) * 256 = 197376 instructions / 1M instructions per second = 0.197 sec. ; call it two-tenths of a second. return end