LIST   p=16F628A
                        __CONFIG    03FF1H
        STATUS          equ         03h
        TRISB           equ         06h
        PORTB           equ         06h
        Reg_1           equ         21h
        Reg_2           equ         22h
        Reg_3           equ         23h
                        org 0
                        bsf         STATUS,5        ;perehodim
                        bcf         STATUS,6        ;v bank1
                        CLRF        TRISB
                        bcf         STATUS,5        ;perehodim
                        bcf         STATUS,6        ;v bank0
                        movlw       b'00000000'     ;stavim
                        movwf       PORTB           ;nizkiy uroven
                        call        delay
                        movlw       b'11111111'     ;stavim
                        movwf       PORTB           ;vysokiy uroven
                        call        delay2
                        goto        Start
       delay            movlw       .173
                        movwf       Reg_1
                        movlw       .19
                        movwf       Reg_2
                        movlw       .6
                        movwf       Reg_3
                        decfsz      Reg_1,F
                        goto        $-1
                        decfsz      Reg_2,F
                        goto        $-3
                        decfsz      Reg_3,F
                        goto        $-5
                        nop
                        nop
                        return

        delay2          movlw       .190
                        movwf       Reg_1
                        movlw       .75
                        movwf       Reg_2
                        movlw       .21
                        movwf       Reg_3
                        decfsz      Reg_1,F
                        goto        $-1
                        decfsz      Reg_2,F
                        goto        $-3
                        decfsz      Reg_3,F
                        goto        $-5
                        nop
                        return

         Start          bsf         STATUS,5        ;perehodim
                        bcf         STATUS,6        ;v bank1
         Start2         CLRF        TRISB
                        bcf         STATUS,5        ;perehodim
                        bcf         STATUS,6        ;v bank0
                        movlw       b'00000000'     ;stavim
                        movwf       PORTB
                        goto        Start2


     
                        end