start
bcf PORTB,8
MOVLW TIME
MOVWF COUNT
loop
DECFSZ COUNT
goto loop
incf sec,1
bsf PORTB,8
movlw 3CH
subwf sec,0
btfsc CARRY,0
goto start
CLRF sec
incf min,1
movlw min
movfw PORTB
movlw 3CH
subwf min,0
BTFSC CARRY,0
goto start
movlw 00H
movfw PORTB
incf hour,1
movlw hour
movfw PORTA
movlw 18H
subwf hour,0
btfsc CARRY,0
goto start
movlw 00H
movfw PORTA
goto start
END