PORTB EQU 06H 
PORTA EQU 05H
CARRY equ 03h 
COUNT equ 08h
TIME  EQU 9FH 
hour equ 00H
min equ 00H
sec equ 00H
start
bcf PORTB,8
MOVLW TIME
MOVWF COUNT
LOOP1
DECFSZ COUNT
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