list p=16F84 ; list directive to define processor #include ; processor specific variable definitions counter equ H'0c' ; A storage location for a software timer call initialize main movlw 2 ;Display first digit movwf PORTA call delay movlw 9 ;Display second digit movwf PORTA call delay movlw 3 ;Display third digit movwf PORTA call delay movlw 6 ;Display fourth digit movwf PORTA call delay movlw 1 ;Display fifth digit movwf PORTA call delay movlw 8 ;Display sixth digit movwf PORTA call delay movlw 1 ;Display seventh digit movwf PORTA call delay goto main ;Repeat forever ; **************************************************** ; One-time initialization code goes here. initialize bsf STATUS,RP0 ; Switch to Bank 1 movlw B'00000000' ; Make all five pins of Ports A and B outputs. movwf TRISA movwf TRISB bcf STATUS,RP0 ; Switch back to Bank 0. return ; **************************************************** ; Delay for some number of cycles. ; Let n0 = counter ; n = # of cycles to waste ; t = time to waste ; T = one instruction period ; Then choose n = t/T = 2 + 2 + 6(n0) + 4 = 8 + 6(n0) ; or ; n0 = (t/T - 8)/6 delay movlw 2 ; This is a dummy value. We'll need to compute the ; correct value to get a 1 s delay. movwf counter delayloop movf counter,F ; See if counter is zero yet. btfsc STATUS,Z return ; It's zero so return decf counter,F ; Decrement the counter and repeat goto delayloop ; **************************************************** end ; This is necessary to tell the assembler the program is done.