#include  <p16f88.inc>

        goto main

init    nop                     ;do nothing
        movlw   b'00000000'     ;move constante value to working register
        movwf   PORTB           ;move value from working register to PORTB
        clrf    PORTA           ;clear file PORTA because they are not used
        bsf     STATUS, RP0     ;switch to RamBank1
        movlw   b'00000000'
        movwf   TRISB           ;set Output
        clrf    TRISA           ;set Output
        bcf     STATUS, RP0     ;switch to RamBank0
        return

main    nop
        call    init            ;start subroutine

main_1  bsf     PORTB,3         ;switch on led
        bcf     PORTB,3         ;switch off led
        goto    main_1

        END