TITLE "Frequency meter/counter" List P=16F913, R=DEC INCLUDE "p16F913.inc" errorlevel -302 ; no bank warnings __CONFIG _DEBUG_OFF & _FCMEN_OFF & _IESO_OFF & _BOD_OFF & _CPD_OFF & _CP_OFF & _MCLRE_OFF & _PWRTE_ON & _WDT_ON & _HS_OSC switch0 EQU LOW 7000 ; switching frequency from couting mode switch1 EQU HIGH 7000 ; to the measuring one ledPin EQU 3 ; pin for lighting up the LEDs (PORTC,3) #define LEDport TRISC,ledPin ; status of the LED lighting pin #define LEDpin PORTC,ledPin ; port for lighting up the LEDs #define LT1719 PORTC,4 ; port for shutting down LT1719 #define POWER PORTA,5 ; port for shutting down the device #define MODBUT PORTE,3 ; button for switching the mode ; DATA SEGMENTS CBLOCK 0x20 period1:3 period:3 ; counter for the period devidend:3 ; storage for 5*10^6 del:2 ; used for delays freq:3 ; counter for the frequency w_save, stat_save, pc_save ; ISR variables err ; error byte its bits are as follows ; 0 - too low freq (much below 1Hz) ; 1 - too high freq (above 15MHz) ; 2 - not used in this version ; 3 - freq counting error ; 4 - need 0.1sec delay after measurement unit ; Hz, KHz, or MHz idle:2 ; idle time counter mode ; enables 1sec measurement intervals debounce:2 ; used for debouncing ENDC CBLOCK 0x70 bcd:4 ; storage for 8 decimal digits lcd:4 ; storage for 4 LCD digits length ; number of decimal digits temp, cnt, dp ; local temporary variables ENDC ; CODE SEGMENT ORG 0 goto main ORG 4 ; interrupt service routine movwf w_save ; save Wreg swapf STATUS, w ; save stat reg without movwf stat_save ; changing flags btfss PIR1, CCP1IF ; CCP1 interrupt? goto tmr1Int ; no startCapture bcf PIR1, CCP1IF ; clear interrupt flag btfsc cnt, 0 ; was it the second interrupt? goto endCapture bsf cnt, 0 ; mark the interrupt as the first one movf CCPR1L, w ; get the first pulse timing movwf period1+0 movf CCPR1H, w movwf period1+1 clrf period1+2 clrf freq+2 goto ISR_end endCapture movlw 2 ; mark interrupt as the second one movwf cnt movf CCPR1L, w ; get the second pulse timing movwf period+0 movf CCPR1H, w movwf period+1 movf freq+2, w movwf period+2 bcf PIR1, TMR1IF goto ISR_end tmr1Int btfss PIR1, TMR1IF ; TMR1 interrupt? goto ISR_end ; no bcf PIR1, TMR1IF ; clear interrupt flag incfsz freq+2, f ; increment interrupt counter goto ISR_end clrf period ; report an error (too low freq) clrf period+1 clrf period+2 bsf err, 0 bsf cnt, 1 ISR_end swapf stat_save, w ; get original flags in STATUS movwf STATUS swapf w_save, f ; restore Wreg swapf w_save, w retfie encode7seg andlw 0x0F ; make sure that bits WREG<7:4> are zeros addwf PCL, f retlw b'01101111' ; code for '0' retlw b'00001001' ; code for '1' retlw b'01110011' ; code for '2' retlw b'01011011' ; code for '3' retlw b'00011101' ; code for '4' retlw b'01011110' ; code for '5' retlw b'01111110' ; code for '6' retlw b'00001011' ; code for '7' retlw b'01111111' ; code for '8' retlw b'01011111' ; code for '9' retlw b'00111101' ; code for 'H' retlw b'01100100' ; code for 'L' retlw b'00110110' ; code for 'F' retlw b'01110110' ; code for 'E' retlw b'00110000' ; code for 'r' retlw b'00010000' ; code for '-' setDecimalPoint andlw 0x0F ; make sure that bits WREG<7:4> are zeros addwf PCL, f retlw 0 ; for length = 0 retlw 0 ; for length = 1 retlw 0 ; for length = 2 retlw 0 ; for length = 3 retlw b'0010' ; for length = 4 (dp.1) retlw b'0100' ; for length = 5 (dp.2) retlw b'1000' ; for length = 6 (dp.3) retlw b'0010' ; for length = 7 (dp.1) retlw b'0010' ; for length = 8 (dp.2) retlw 0 ; the remaining values are meaningless retlw 0 ; and are added to prevent a jump retlw 0 ; to a wrong place in the code retlw 0 retlw 0 retlw 0 retlw 0 displaySymbol ; symbol is in WREG call encode7seg ; get 7-digit code movwf temp ; and save it in temp movf cnt, w ; select LCD digit to update sublw 4 ; depending on the value of cnt addwf PCL, f goto displayDig1 ; each of those jumps provides a return goto displayDig2 goto displayDig3 goto displayDig4 main clrf PORTA ; initialize the I/O potrs clrf PORTB clrf PORTC bsf LT1719 ; turn off LT1719 bsf POWER ; turn on the unit bsf MODBUT clrwdt bsf STATUS, RP0 ; change to BANK 1 movlw 7 movwf CMCON0 ; comparators off clrf ANSEL ^ 0x80 ; all inputs digital clrf OSCCON ^ 0x80 ; oscillator configuration bits clrf TRISA ^ 0x80 ; STEP 1 clrf TRISB ^ 0x80 ; setup all pins for output clrf TRISC ^ 0x80 ; with the only exception of the bsf TRISC ^ 0x80, 5 ; TMR1/CCP1 input pin (and PORTE:3) bcf STATUS, RP0 bsf STATUS, RP1 ; change to BANK 2 bsf LCDCON ^ 0x100, VLCDEN ; STEP 2: enable LCD bias voltage pins bsf LCDCON ^ 0x100, CS1 ; STEP 3: select clock source (lfintosc) bcf LCDCON ^ 0x100, CS0 bsf LCDCON ^ 0x100, LMUX1 ; STEP 4: select multiplex mode (1/3) bcf LCDCON ^ 0x100, LMUX0 bcf LCDPS, WFT ; STEP 5: select waveform type (A) bcf LCDPS, BIASMD ; STEP 6: select Bias mode (1/3) bcf LCDPS, LP3 ; STEP 7: select refresh rate bsf LCDPS, LP2 ; prescaler 1:8 for 43Hz bsf LCDPS, LP1 bsf LCDPS, LP0 movlw b'10011111' ; step 8: enable LCD segment lines movwf LCDSE0 movlw b'11110011' movwf LCDSE1 clrf LCDDATA0 ^ 0x100 ; step 9: clear segment data registers clrf LCDDATA1 ^ 0x100 clrf LCDDATA3 ^ 0x100 clrf LCDDATA4 ^ 0x100 clrf LCDDATA6 ^ 0x100 clrf LCDDATA7 ^ 0x100 bsf LCDCON ^ 0x100, LCDEN ; step 10: turn on the LCD driver module bcf LCDCON ^ 0x100, SLPEN ; enable LCD in sleep mode movlw b'10100' ; set Watchdog prescaler 1:32768 movwf WDTCON ; for a reset period of approx. 1 sec bsf STATUS, RP0 ; switch to BANK 4 bsf OPTION_REG, PSA ; assign prescaler to watchdog movlw 0xF8 andwf OPTION_REG, f ; set WDT/TMR0 prescaler 1:2 bsf OPTION_REG, 0 WDTrecover bcf STATUS, RP0 ; back to BANK 0 bcf STATUS, RP1 bcf INTCON, GIE ; disable all interrupts clrf CCP1CON ; turn off the CCP module bsf INTCON, PEIE ; enable periferal interrupts clrf PIR1 ; clear all interrupt flags clrf freq ; initialize freq with 0 clrf freq+1 clrf freq+2 clrf mode clrf err clrf unit clrf idle clrf idle+1 goto entry2 ; display initial 0 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; loop ; MAIN LOOP btfsc MODBUT ; check the button status goto entry1 call wait4Release ; wait for the button release movlw 1 xorwf mode, f ; toggle the mode status entry1 clrf err ; reset all error flags clrf unit ; initialize the unit (Hz, KHz, MHz) bcf LT1719 ; turn on LT1719 call delay1msec ; let LT1719 wake up call countFreq ; get frequency count bsf LT1719 ; shut down LT1719 call countIdleCycles ; check if the counter is idle (freq=0) entry2 call freq2BCD ; convert freq into BCD representation call displayFreq ; send the data to LCD call delay100msec btfsc err, 4 ; need a delay? call delay100msec goto loop ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; countFreq bsf T1CON, TMR1CS ; set external clock for TMR1 bsf T1CON, T1SYNC ; no SYNC clrf dp ; decimal point correction movlw 1 movwf cnt call countPulses ; apply a 1msec interval first analyseFreq ; select a correct counting interval movlw LOW 15000 ; check if freq count >= 15000 subwf freq, w ; in this case report the error movlw HIGH 15000 ; because the real freq if above 15MHz movwf temp btfss STATUS, C incfsz temp, w subwf freq+1, w btfss STATUS, C goto below15MHz bsf err, 4 ; need a delay to slow down bsf err, 1 ; report a too high frequency movlw 5 ; rounding constant bsf unit, 2 ; display MHz goto roundFreq ; frequency has 5 decimal digits below15MHz movlw LOW 10000 ; check if freq count >= 10000 subwf freq, w ; in this case the real freq is above 10MHz movlw HIGH 10000 movwf temp btfss STATUS, C incfsz temp, w subwf freq+1, w btfss STATUS, C goto below10MHz bsf err, 4 ; need a delay to slow down movlw 5 ; rounding constant bsf unit, 2 ; display MHz goto roundFreq ; frequency has 5 decimal digits (above 10MHz) below10MHz movlw LOW 1000 subwf freq, w ; 16-bit subtract movlw HIGH 1000 movwf temp btfss STATUS, C incfsz temp, w subwf freq+1, w btfss STATUS, C goto below1MHz ; counted in 1msec frequency has 3 decimal digits movlw 2 ; at this point freq has 4 decimal digits movwf cnt ; so is between 1Mhz and 10MHz call countPulses ; apply a 10msec interval to make it 5-digits movlw -1 ; decimal point correction movwf dp ; e.g. 1.2345 bsf err, 4 ; need a delay to slow down movlw 5 ; rounding constant bsf unit, 2 ; display MHz goto roundFreq ; we know that freq count has 5 digits below1MHz ; measuring freqiencies below 1MHz movlw 4 ; apply a 100msec counting interval movwf cnt call countPulses movf freq, w ; if the freq is 0 we are done and do not addwf freq+1, w ; measure the freq below 10Hz btfsc STATUS, Z return ; at this point freq has up to 5 decimal digits movlw LOW 10000 ; check if freq count >= 10000 (5 digits) subwf freq, w ; in this case the rounding constant movlw HIGH 10000 ; is 50 and the decimal point correction =1 movwf temp ; and the input frequency is above 100KHz btfss STATUS, C incfsz temp, w subwf freq+1, w btfss STATUS, C goto below100KHz movlw 1 ; here the freq count is 5-digit movwf dp ; dp correction (in reality freq is 6-digit) movlw 50 ; rounding constant bsf unit, 1 ; display KHz goto roundFreq below100KHz movlw LOW 1000 ; check if freq count >= 1000 (4 digits) subwf freq, w ; in this case the rounding constant movlw HIGH 1000 ; is 0 and the decimal point correction =1 movwf temp ; and the input frequency is below 100KHz btfss STATUS, C incfsz temp, w subwf freq+1, w btfss STATUS, C goto below10KHz movlw 1 ; here the freq count is 4-digit movwf dp ; dp correction (in reality freq is 5-digit) clrw ; rounding constant bsf unit, 1 ; display KHz goto roundFreq below10KHz ; this is the range where we switch from counting btfss mode, 0 ; is 1-sec mode enabled? goto checkSwitching ; NO movlw 8 ; otherwise, apply a 1sec counting interval movwf cnt call countPulses clrf dp ; no dp corretion is needed movlw 1 movwf unit ; Hz movlw LOW 1000 ; check if freq count >= 1000 subwf freq, w ; to correctly display the unit (Hz or KHz) movlw HIGH 1000 movwf temp btfss STATUS, C incfsz temp, w subwf freq+1, w btfsc STATUS, C incf unit, f ; KHz return checkSwitching movlw switch0 ; number of pulses to measuring the period subwf freq, w ; check if the freq is above the switching point movlw switch1 ; given by switch1:switch0 movwf temp btfss STATUS, C incfsz temp, w subwf freq+1, w btfss STATUS, C goto measureFreq ; goto measuring the period aboveSwitching bcf STATUS, C ; in this case we need to multipy freq by 10 rlf freq, f ; to have 4 digits to display rlf freq+1, f ; the input freq is below 10KHz and above the movf freq, w ; switching point 7KHz, so it is only 3 digits movwf bcd ; by counting it for 0.1sec movf freq+1, w movwf bcd+1 ; bcd = freq*2 (2 bytes) rlf freq, f rlf freq+1, f rlf freq, f rlf freq+1, f ; freq *= 8 movf bcd, w addwf freq, f movf bcd+1, w btfsc STATUS, C addlw 1 addwf freq+1, f ; freq *= 10 clrw ; rounding constant bsf unit, 1 ; display KHz roundFreq addwf freq, f ; only 4 high-order digits will be shown clrw btfsc STATUS, C addlw 1 ; correct C-bit is not needed addwf freq+1, f return ;************************************************************************** measureFreq ; measure the period of freq below 7KHz clrwdt clrf dp bcf T1CON, TMR1CS ; set internal clock movlw 4 ; turn on the CCP module and movwf CCP1CON ; enable capture mode on falling edge clrf PIR1 ; clear CCP1 and TMR1 interrupt flags bsf STATUS, RP0 ; switch to BANK 1 bsf PIE1, CCP1IE ; enable CCP1 interrupt bsf PIE1, TMR1IE ; enable TMR1 interrupt bcf STATUS, RP0 ; back to BANK 0 clrf freq+2 bsf T1CON, TMR1ON ; enable counting clrf cnt clrf PIR1 ; clear all interrupt flags bsf INTCON, GIE ; enable global interrupts btfss cnt, 1 ; wait for 2 input pulses goto $-1 bcf INTCON, GIE ; disable interrupts clrf PIR1 ; and clear all interrupt flags bcf T1CON, TMR1ON ; disable counting bsf STATUS, RP0 ; switch to BANK 1 bcf PIE1, CCP1IE ; disable CCP1 interrupt bcf PIE1, TMR1IE ; disable TMR1 interrupt bcf STATUS, RP0 ; back to BANK 0 clrf CCP1CON ; turn off the CCP module clrf PIR1 ; clear all interrupt flags movf period1+0, w ; 24-bit subtract subwf period+0, f movf period1+1, w btfss STATUS, C incfsz period1+1, w subwf period+1, f movf period1+2, w btfss STATUS, C incfsz period1+2, w subwf period+2, f ; subtraction is completed movlw b'01001100' ; load the devidend = 5*10^6 movwf devidend+2 ; to perform the division of movlw b'01001011' ; 5*10^6 over the measured period movwf devidend+1 ; to get the frequency value in Hz movlw b'01000000' movwf devidend clrf freq+2 ; clear the result clrf freq+1 clrf freq shift movlw 1 movwf cnt ; divide 5*10^6 / period btfsc period+2, 6 ; to get the quotient in freq goto divide ; (at most 14 bits) bcf STATUS, C rlf period, f ; rotate the period to put its MSB rlf period+1, f ; below the one in devidend rlf period+2, f incf cnt, f goto shift+2 divide movf period, w ; 24-bit subtract subwf devidend, f movf period+1, w btfss STATUS, C incfsz period+1, w subwf devidend+1, f movf period+2, w btfss STATUS, C incfsz period+2, w subwf devidend+2, f ; subtraction is completed rlf freq, f ; shift in the result (status bit) rlf freq+1, f ; into the quotient (it is at most 14 bits) btfsc freq, 0 goto checkCount movf period, w ; restore the devidend addwf devidend, f movf period+1, w btfsc STATUS, C incfsz period+1, w addwf devidend+1, f movf period+2, w btfsc STATUS, C addlw 1 ; here the correct C bit is not needed addwf devidend+2, f checkCount decf cnt, f btfsc STATUS, Z goto round bcf STATUS, C ; shift the devisor 1 bit to the right rrf period+2, f rrf period+1, f rrf period, f goto divide round bcf STATUS, C ; check if the remainder is at least a rlf devidend, f ; half of the period and add 1 to the rlf devidend+1, f ; result in this case movf period, w ; 16-bit subtract subwf devidend, f movf period+1, w btfss STATUS, C incfsz period+1, w subwf devidend+1, f btfss STATUS, C ; if C=0 no rounding is needed goto checkUnit incf freq, f ; increment the quotient (at most 14 bits) btfsc STATUS, Z incf freq+1, f checkUnit movlw 1 movwf unit movlw LOW 1000 subwf freq, w ; check if the freq is above 1000 movlw HIGH 1000 movwf temp btfss STATUS, C incfsz temp, w subwf freq+1, w btfsc STATUS, C incf unit, f return ;------------------------------------------------------------------------- countPulses ; bits 0-2 of cnt determine the delay clrwdt clrf TMR1L ; clear the TMR1 counter clrf TMR1H bsf T1CON, TMR1ON ; enable TMR1 for counting btfss cnt, 0 ; select the delay goto $+3 ; cnt=1: delay=1msec call delay1msec ; cnt=2: delay=10msec goto getCount ; cnt=3: delay=100msec btfss cnt, 1 goto $+3 call delay10msec goto getCount btfss cnt, 2 goto $+3 call delay100msec goto getCount call delay1sec getCount bcf T1CON, TMR1ON ; disable TMR1 for counting movf TMR1L, w ; get the TMR1 value in freq+1:freq movwf freq ; and leave freq+2 = 0 movf TMR1H, w movwf freq+1 ; at this point the freq counter is set clrf freq+2 ; clear interrupt counter return delay1msec movlw 111 ; settings for a 0.001sec delay movwf del movlw 3 movwf del+1 movlw 1 ; this fragment takes 5000 instruction subwf del, f ; cycles and provides a 1msec delay btfsc STATUS, Z ; by running PIC at 20MHz decf del+1, f movf del+1, w btfss STATUS, Z goto $-6 goto $+1 goto $+1 nop return delay10msec movlw 104 ; settings for a 0.01sec delay movwf del movlw 25 movwf del+1 movlw 1 ; this fragment takes 50000 instruction subwf del, f ; cycles and provides a 10msec delay btfsc STATUS, Z ; by running PIC at 20MHz decf del+1, f movf del+1, w btfss STATUS, Z goto $-6 goto $+1 return delay100msec movlw 33 ; settings for a 0.1sec delay movwf del movlw 245 movwf del+1 movlw 1 ; this fragment takes 500000 instruction subwf del, f ; cycles and provides a 100msec delay btfsc STATUS, Z ; by running PIC at 20MHz decf del+1, f movf del+1, w btfss STATUS, Z goto $-6 goto $+1 goto $+1 goto $+1 nop return delay1sec movlw 1 ; settings for a 1sec delay movwf del movlw 49 movwf del+1 movlw 16 movwf temp movlw 1 ; this fragment takes 5000000 instruction subwf del, f ; cycles and provides a 1sec delay btfss STATUS, Z ; by running PIC at 20MHz goto $-3 decf del+1, f btfsc STATUS, Z decf temp, f movf temp, w btfss STATUS, Z goto $-9 goto $+1 nop return checkByte movlw 0xF0 andwf temp, w btfsc del, 0 goto $+4 btfsc STATUS, Z goto nextNybble bsf del, 0 incf length, f decf cnt, f btfsc cnt, 7 goto nextNybble movwf INDF swapf INDF, f decf FSR, f nextNybble movlw 0x0F andwf temp, w btfsc del, 0 goto $+4 btfsc STATUS, Z return bsf del, 0 incf length, f decf cnt, f btfsc cnt, 7 return movwf INDF decf FSR, f return freq2BCD clrwdt movlw 24 ; 24-bits movwf temp ; make cycle counter clrf bcd ; clear result area clrf bcd+1 clrf bcd+2 clrf bcd+3 b2bcd2 movlw bcd ; make pointer movwf FSR movlw 4 movwf cnt b2bcd3 movlw 0x33 addwf INDF, f ; add to both nybbles btfsc INDF, 3 ; test if low result > 7 andlw 0xF0 ; low result >7 so take the 3 out btfsc INDF, 7 ; test if high result > 7 andlw 0x0F ; high result > 7 so ok subwf INDF, f ; any results <= 7, subtract back incf FSR, f ; point to next decfsz cnt, f goto b2bcd3 rlf freq+0, f ; get another bit rlf freq+1, f rlf freq+2, f rlf bcd+3, f ; put it into bcd rlf bcd+2, f rlf bcd+1, f rlf bcd+0, f decfsz temp, f ; all done? goto b2bcd2 ; no, loop return ; yes processErrors ; display error messages btfss err, 0 ; too low freq? goto tooHigh movlw 11 ; code of L call encode7seg movwf temp call displayDig2 movlw 12 ; code of F call encode7seg movwf temp call displayDig3 return tooHigh btfss err, 1 ; too high freq? goto someError movlw 10 ; code of H call encode7seg movwf temp call displayDig2 movlw 12 ; code of F call encode7seg movwf temp call displayDig3 return someError ; display Err_ movlw 13 call encode7seg movwf temp ; code of E call displayDig1 movlw 14 ; code of r call encode7seg movwf temp call displayDig2 call displayDig3 return displayFreq clrwdt bsf STATUS, RP1 ; switch to BANK 2 clrf LCDDATA0 ; clear all used segment data regs clrf LCDDATA1 ; this will clear the display clrf LCDDATA3 clrf LCDDATA4 clrf LCDDATA6 clrf LCDDATA7 bcf STATUS, RP1 ; back to BANK 0 movlw b'1011' ; check for errors and display them andwf err, w btfss STATUS, Z goto processErrors ; ... and return from there clrf length ; digits counter clrf del clrf lcd+3 ; needed to display 0 if freq=0 movlw 4 movwf cnt ; number of digits to copy movlw lcd+3 movwf FSR ; set pointer to the lcd array movf bcd+0, w movwf temp call checkByte movf bcd+1, w movwf temp call checkByte movf bcd+2, w movwf temp call checkByte movf bcd+3, w movwf temp call checkByte movf dp, w addwf length, w call setDecimalPoint movwf dp spaces movlw lcd+3 ; put indirect pointer to the first movwf FSR ; lcd digit movlw 4 ; cnt = # of symbols to display movwf cnt subwf length, w ; >= 4 digits? btfsc STATUS, C goto displayDigits sublw 0 ; w = number of spaces (4 - length) > 0 movwf length ; in this case we display spaces decf cnt, f decf length, f btfsc STATUS, Z goto displayDigits decf cnt, f decf length, f btfsc STATUS, Z goto displayDigits decf cnt, f displayDigits ; take the next cnt digits from lcd movf INDF, w decf FSR, f call displaySymbol decf cnt, f btfss STATUS, Z goto displayDigits call showUnits return displayDig1 ; displaying the first digit (the leftmost one) bsf STATUS, RP1 ; switch to BANK 2 btfsc temp, 3 ; setup for COM0 bsf LCDDATA0, 4 btfsc temp, 4 bsf LCDDATA1, 0 btfsc temp, 5 bsf LCDDATA1, 1 btfsc temp, 0 ; setup for COM1 bsf LCDDATA3, 4 btfsc temp, 1 bsf LCDDATA4, 0 btfsc temp, 2 bsf LCDDATA4, 1 btfsc temp, 6 ; setup for COM2 bsf LCDDATA7, 0 btfsc dp, 1 ; decimal point? bsf LCDDATA6, 4 bcf STATUS, RP1 ; switch to BANK 0 return displayDig2 bsf STATUS, RP1 ; switch to BANK 2 btfsc temp, 3 ; setup for COM0 bsf LCDDATA1, 7 btfsc temp, 4 bsf LCDDATA0, 1 btfsc temp, 5 bsf LCDDATA0, 0 btfsc temp, 0 ; setup for COM1 bsf LCDDATA4, 7 btfsc temp, 1 bsf LCDDATA3, 1 btfsc temp, 2 bsf LCDDATA3, 0 btfsc temp, 6 ; setup for COM2 bsf LCDDATA6, 1 btfsc dp, 2 ; decimal point? bsf LCDDATA7, 7 bcf STATUS, RP1 ; switch to BANK 0 return displayDig3 bsf STATUS, RP1 ; switch to BANK 2 btfsc temp, 3 ; setup for COM0 bsf LCDDATA0, 7 btfsc temp, 4 bsf LCDDATA0, 3 btfsc temp, 5 bsf LCDDATA0, 2 btfsc temp, 0 ; setup for COM1 bsf LCDDATA3, 7 btfsc temp, 1 bsf LCDDATA3, 3 btfsc temp, 2 bsf LCDDATA3, 2 btfsc temp, 6 ; setup for COM2 bsf LCDDATA6, 3 btfsc dp, 3 ; decimal point? bsf LCDDATA6, 7 bcf STATUS, RP1 ; switch to BANK 0 return displayDig4 bsf STATUS, RP1 ; switch to BANK 2 btfsc temp, 3 ; setup for COM0 bsf LCDDATA1, 4 btfsc temp, 4 bsf LCDDATA1, 5 btfsc temp, 5 bsf LCDDATA1, 6 btfsc temp, 0 ; setup for COM1 bsf LCDDATA4, 4 btfsc temp, 1 bsf LCDDATA4, 5 btfsc temp, 2 bsf LCDDATA4, 6 btfsc temp, 6 ; setup for COM2 bsf LCDDATA7, 5 bcf STATUS, RP1 ; switch to BANK 0 return showUnits ; display Hz, KHz, or MGz btfss unit, 0 ; check for Hz goto $+6 bsf STATUS, RP0 ; switch to BANK 1 bcf LEDport ; configure the pin for output bcf STATUS, RP0 ; back to BANK 0 bcf LEDpin ; turn on green LED return btfss unit, 1 ; check for KHz goto $+5 ; and turn on both LEDs bsf STATUS, RP0 ; switch to BANK 1 bsf LEDport ; configure the pin for input bcf STATUS, RP0 ; back to BANK 0 return bsf STATUS, RP0 ; switch to BANK 1 bcf LEDport ; configure the pin for output bcf STATUS, RP0 ; back to BANK 0 bsf LEDpin ; turn the red LED return countIdleCycles movf freq, w iorwf freq+1, w iorwf freq+2, w ; W=0 iff freq=0 btfss STATUS, Z goto resetIdle bsf unit, 0 ; set Hz incf idle, f ; increment idle counter btfsc STATUS, Z incf idle+1, f btfsc idle+1, 2 bcf POWER return resetIdle clrf idle clrf idle+1 return wait4Release clrf debounce ; wait for the button release clrf debounce+1 btfss MODBUT ; button released? goto wait4Release ; NO - wait for release incf debounce, f btfsc STATUS, Z incf debounce+1, f btfss debounce+1, 6 ; 30msec goto $-6 return END