TITLE "wind.asm" ; anemometer List P=PIC16F648A, R=DEC INCLUDE "p16f648a.inc" ERRORLEVEL -302 ; no bank warnings __CONFIG _CP_OFF & _DATA_CP_OFF & _LVP_OFF & _BOREN_OFF & _MCLRE_OFF & _PWRTE_ON & _WDT_OFF & _INTOSC_OSC_NOCLKOUT ; data segment CBLOCK 0x20 del, t1 ; variables used for delay wind ; wind sensor counter temp ; local variables w_save, stat_save ; locations to save W and STATUS in ISR tens, units ; storage for decimal digits ENDC ; code segment ORG 0 ; start program at the beginning of mem goto main ORG 4 ; Interrupt Service Routie movwf w_save ; save W reg swapf STATUS, w ; save stat reg without movwf stat_save ; changing flags incf t1, f ; count 8 TMR1 interrupts btfss t1, 3 ; corresponding to a 4 sec interval goto ISR_END clrf t1 movf TMR0, w ; get pulse count clrf TMR0 sublw 99 ; if the number exceeds 100 btfss STATUS, C ; bound it with 99 clrw sublw 99 btfss PORTA, 1 ; check the mode goto mode3 ; given by the swicthes at btfsc PORTA, 0 ; RA1 and RA0 goto mode2 mode1 ; convertion to km/h clrf temp sublw 2 ; set decimal point if the number of pulses btfsc STATUS, C ; does not exceed 2 incf temp, f sublw 2 ; restore w call convert1 goto process mode2 ; conversion to m/s clrf temp sublw 45 ; set decimal point if the number of pulses btfsc STATUS, C ; does not exceed 45 incf temp, f sublw 45 ; restore w call convert2 goto process mode3 ; pulse count mode call bin2BCD ; convert pulse count into BCD goto ISR_END process clrf PCLATH movwf tens ; save table conversion results movwf units swapf tens, f ; extract tens movlw 0x0F andwf tens, f andwf units, f ; extract units btfsc temp, 0 ; check for decimal point bsf tens, 4 ; ebmed it into bit 4 of tens ISR_END bcf PIR1, TMR1IF ; clear interrupt flag swapf stat_save, w ; get orig flags in STATUS movwf STATUS swapf w_save, f ; restore the original W swapf w_save, w retfie main ; main code bcf STATUS, RP0 ; activate BANK 0 clrf PORTA ; initialize PORT A clrf PORTB ; initialize PORT B movlw 0x07 movwf CMCON ; comparators OFF bsf STATUS, RP0 ; change to BANK 1 movlw b'00111000' movwf OPTION_REG ^ 0x80 ; TMR0 setup movlw b'00110011' movwf TRISA ^ 0x80 ; enable output on PORTA<7:6, 3:2> clrf TRISB ^ 0x80 ; enable output on PORTB 0 bsf PIE1, TMR1IE ; enable TMR1 interrupts bcf STATUS, RP0 ; back to BANK 0 bsf INTCON, PEIE bcf PIR1, TMR1IF ; clear TMR1 IF clrf TMR1H clrf TMR1L clrf TMR0 movlw b'00110001' ; TMR1 setup: 1:8 divider, FOSC/4 movwf T1CON clrf t1 bsf INTCON, GIE ; enable interrupts globally clrf wind ; clear the wind counter clrf tens bsf tens, 4 clrf units loop ; main loop movf tens, w call encode7seg ; get 7-seg code in WREG btfsc tens, 4 ; check if dp must be on addlw 2 ; turn of dp bcf PORTA, 7 ; turn off units movwf PORTB ; update display bsf PORTA, 6 ; turn on tens call delay ; 7 msec delay movf units, w call encode7seg ; get 7-seg code in WREG bcf PORTA, 6 ; turn off tens movwf PORTB ; update display bsf PORTA, 7 ; turn on units call delay ; 7 msec delay goto loop bin2BCD ; convert a 2-digit decimal value in BCD movwf temp clrf tens movlw 10 subwf temp, f ; subtract 10 from the counter incf tens, f ; until we get a negative result btfsc STATUS, C goto $-3 decf tens, f ; adjust the tens counter addwf temp, w movwf units ; obtain units return delay ; a delay for del milliseconds movlw 7 movwf del movlw 250 addlw -1 ; this loop takes 4us*250 = 1ms btfss STATUS, Z ; for PIC @ 4 Mhz goto $-2 decfsz del, f goto delay+2 return encode7seg ; abgfdepc andlw 0x0F addwf PCL, f ; bit 1 is the decimal point retlw b'11011101' ; code for 0 retlw b'01000001' ; code for 1 retlw b'11101100' ; code for 2 retlw b'11101001' ; code for 3 retlw b'01110001' ; code for 4 retlw b'10111001' ; code for 5 retlw b'10111101' ; code for 6 retlw b'11000001' ; code for 7 retlw b'11111101' ; code for 8 retlw b'11111001' ; code for 9 retlw b'00000000' ; blank retlw b'00000000' ; blank retlw b'00000000' ; blank retlw b'00000000' ; blank retlw b'00000000' ; blank retlw b'00000000' ; blank ORG 0x100 convert1 ; conversion table for km/h clrf PCLATH incf PCLATH, f addwf PCL, f retlw 0x00 retlw 0x87 retlw 0x94 retlw 0x10 retlw 0x11 retlw 0x11 retlw 0x12 retlw 0x12 retlw 0x13 retlw 0x14 retlw 0x14 retlw 0x15 retlw 0x16 retlw 0x16 retlw 0x17 retlw 0x17 retlw 0x18 retlw 0x19 retlw 0x19 retlw 0x20 retlw 0x20 retlw 0x21 retlw 0x22 retlw 0x22 retlw 0x23 retlw 0x23 retlw 0x24 retlw 0x25 retlw 0x25 retlw 0x26 retlw 0x27 retlw 0x27 retlw 0x28 retlw 0x28 retlw 0x29 retlw 0x30 retlw 0x30 retlw 0x31 retlw 0x31 retlw 0x32 retlw 0x33 retlw 0x33 retlw 0x34 retlw 0x35 retlw 0x35 retlw 0x36 retlw 0x36 retlw 0x37 retlw 0x38 retlw 0x38 retlw 0x39 retlw 0x39 retlw 0x40 retlw 0x41 retlw 0x41 retlw 0x42 retlw 0x43 retlw 0x43 retlw 0x44 retlw 0x44 retlw 0x45 retlw 0x46 retlw 0x46 retlw 0x47 retlw 0x47 retlw 0x48 retlw 0x49 retlw 0x49 retlw 0x50 retlw 0x51 retlw 0x51 retlw 0x52 retlw 0x52 retlw 0x53 retlw 0x54 retlw 0x54 retlw 0x55 retlw 0x55 retlw 0x56 retlw 0x57 retlw 0x57 retlw 0x58 retlw 0x59 retlw 0x59 retlw 0x60 retlw 0x60 retlw 0x61 retlw 0x62 retlw 0x62 retlw 0x63 retlw 0x63 retlw 0x64 retlw 0x65 retlw 0x65 retlw 0x66 retlw 0x66 retlw 0x67 retlw 0x68 retlw 0x68 retlw 0x69 convert2 ; conversion table for m/s clrf PCLATH incf PCLATH, f addwf PCL, f retlw 0x00 retlw 0x24 retlw 0x26 retlw 0x28 retlw 0x29 retlw 0x31 retlw 0x33 retlw 0x35 retlw 0x36 retlw 0x38 retlw 0x40 retlw 0x41 retlw 0x43 retlw 0x45 retlw 0x46 retlw 0x48 retlw 0x50 retlw 0x52 retlw 0x53 retlw 0x55 retlw 0x57 retlw 0x58 retlw 0x60 retlw 0x62 retlw 0x64 retlw 0x65 retlw 0x67 retlw 0x69 retlw 0x70 retlw 0x72 retlw 0x74 retlw 0x75 retlw 0x77 retlw 0x79 retlw 0x81 retlw 0x82 retlw 0x84 retlw 0x86 retlw 0x87 retlw 0x89 retlw 0x91 retlw 0x93 retlw 0x94 retlw 0x96 retlw 0x98 retlw 0x99 retlw 0x10 retlw 0x10 retlw 0x10 retlw 0x11 retlw 0x11 retlw 0x11 retlw 0x11 retlw 0x11 retlw 0x11 retlw 0x12 retlw 0x12 retlw 0x12 retlw 0x12 retlw 0x12 retlw 0x12 retlw 0x13 retlw 0x13 retlw 0x13 retlw 0x13 retlw 0x13 retlw 0x14 retlw 0x14 retlw 0x14 retlw 0x14 retlw 0x14 retlw 0x14 retlw 0x15 retlw 0x15 retlw 0x15 retlw 0x15 retlw 0x15 retlw 0x15 retlw 0x16 retlw 0x16 retlw 0x16 retlw 0x16 retlw 0x16 retlw 0x16 retlw 0x17 retlw 0x17 retlw 0x17 retlw 0x17 retlw 0x17 retlw 0x17 retlw 0x18 retlw 0x18 retlw 0x18 retlw 0x18 retlw 0x18 retlw 0x18 retlw 0x19 retlw 0x19 retlw 0x19 retlw 0x19 end