list p=16f870A ; list directive to define processor #include ; processor specific variable definitions errorlevel -302 ; Register not in bank 0 warning radix dec __CONFIG _CP_OFF & _WDT_OFF & _BODEN_OFF & _PWRTE_ON & _HS_OSC & _LVP_OFF & _DEBUG_OFF & _CPD_OFF #define VERS 043 ;Version to display ; Data storange org 20h wsave equ 20H ssave equ 21H bitcnt equ 22H ; flag equ 23H count equ 24H scount equ 25H csave equ 26H ddata equ 27H ; was data sdata equ 28H temp equ 29H ontime equ 2BH oftime equ 2CH isrvec equ 2DH qtime equ 2EH ;comm timer for serial timer equ 30H freq equ 33H ; pwmp equ 35H mode equ 36H rate equ 37H baud equ 38H midic equ 39H ;midi channel pmode equ 3AH hi equ 3BH lo equ 3CH ; was low rand equ 3DH acc equ 40H ;32 bit register acc+0(40H)_MSB acc+3(43H)_LSB xacc equ 44H ;aux 32 bit value digits equ 48H ;segment data for LED dignr equ 4CH dp equ 4DH ftimer equ 4EH segmask equ 50H dela equ 51H bcd equ 54H ;10 digit packed bcd buffer (5 bytes) ;pto equ 59H ; not used ;pti equ 5AH ; not used cnt equ 59H ; 5BH ii equ 5AH frame equ 5BH place equ 5Ch port_temp equ 5Dh ; Program Start org 0 goto start ; Table for number to seven segment conversion digseg addwf PCL,f retlw 3fh ;0 retlw 6h ;1 retlw 5bh ;2 retlw 4fh ;3 retlw 66h ;4 retlw 6dh ;5 retlw 7dh ;6 retlw 7h ;7 retlw 7fh ;8 retlw 67h ;9 ; Get anode value for PORT C output getano addwf PCL,f retlw 1 retlw 2 retlw 4 retlw 8 getdp addwf PCL,f retlw 03h retlw 03h retlw 03h retlw 03h retlw 94h retlw 0A5h retlw 0C6h retlw 0D7h retlw 0E8h retlw 0F9h start bsf STATUS,5 movlw b'00111111' movwf TRISA movlw 0 movwf TRISB movlw b'10110000' movwf TRISC movlw b'10001000' movwf OPTION_REG bcf STATUS,5 clrf segmask bsf segmask,0 clrf dignr clrf rate ;added to decrease the scan rate for viewing call signon goto start ; show version No signon movlw VERS call wtod ;put version No movlw 0 movwf digits call sign return ; delay function delay movwf dela+2 dld2 movwf dela+1 dld1 movwf dela dld0 decfsz dela,f goto dld0 decfsz dela+1,f goto dld1 decfsz dela+2,f goto dld2 return ; show 8 bit value on display wtod movwf acc clrf acc+1 clrf acc+2 clrf acc+3 call b2bcd call format return sign movlw .30 movwf temp x1 call segout incf rate,f movf rate,w ;decrease scan rate across display call delay decfsz count,f goto x1 decfsz temp,f goto x1 return ; Convert 32-bit binary number at into a bcd number ; at . Uses Mike Keitz's procedure for handling bcd ; adjust; Modified Microchip AN526 for 32-bits. b2bcd movlw 32 ; 32-bits movwf ii ; make cycle counter clrf bcd ; clear result area clrf bcd+1 clrf bcd+2 clrf bcd+3 clrf bcd+4 b2bcd2 movlw bcd ; make pointer movwf FSR movlw 5 movwf cnt ; Mike's routine_ b2bcd3 movlw 33h addwf 0,f ; add to both nybbles btfsc 0,3 ; test if low result > 7 andlw 0f0h ; low result >7 so take the 3 out btfsc 0,7 ; test if high result > 7 andlw 0fh ; high result > 7 so ok subwf 0,f ; any results <= 7, subtract back incf FSR,f ; point to next decfsz cnt,f goto b2bcd3 rlf acc+0,f ; get another bit rlf acc+1,f rlf acc+2,f rlf acc+3,f rlf bcd+0,f ; put it into bcd rlf bcd+1,f rlf bcd+2,f rlf bcd+3,f rlf bcd+4,f decfsz ii,f ; all done? goto b2bcd2 ; no, loop return ; cycle thru individual segment drives on 4 digits ; (constant execution time_ 30 instructions) ; ************** Do Not Modify ******************* segout movlw 0F0h andwf PORTC,f ;clear low 4 bits movf dignr,w ;get digit nr addlw digits ;base of segment list movwf FSR movf 0,w ;get the data andwf segmask,w ;mask the bit xorlw 0ffh ;invert movwf PORTB ;one possible segment line low movf dignr,w call getano iorwf PORTC,f ; set one high. bcf STATUS,C rlf segmask,f btfsc STATUS,C goto nseg nop nop nop nop nop return nseg bsf segmask,0 ;rotate incf dignr,f btfsc dignr,2 ;overflow? clrf dignr return ; format first 4 signifcant digits on display format call first ;find 1st non-zero digit ffx movf count,w call getdp ;get formating info movwf dp andlw 0fh movwf count ff5 call ff9 ;get segment pattern movwf digits call ff9 movwf digits+1 call ff9 movwf digits+2 call ff9 movwf digits+3 return ff9 movf count,w decf count,f call getbd ;get bcd value call digseg return ; set count to 1st non zero digit first movlw 9 ;start w/last digit movwf count ff2 movf count,w ;get next digit call getbd xorlw 0 ;set z flag btfss STATUS,Z return ;hit non zero decfsz count,f goto ff2 return ; get bcd digit specified by 'w' getbd movwf temp ;save digit nr clrw btfsc temp,7 ;negative value? return ;zero if negative. bcf STATUS,C rrf temp,f ;find buffer offset movf temp,w rlf temp,f ;restore all bits addlw bcd ;add start of bcd buff movwf FSR ;set pointer movf 0,w ;get the byte movwf ddata ;and store it. btfsc temp,0 ;low or hi nibble? swapf ddata,f ;hi. movf ddata,w andlw 0fh return end