;This source was written in orGASM

        org 100h



start:

        mov     al, 13h

        int        10h



        lds bp,[bx]



        dec     byte [si]



drawloop:

        adc     si, 2

        adc     si, 3 

        add     byte [si], 3

        adc     si, 3

        adc     si, 3

        add      byte [si], 3

        neg     si



        jmp     drawloop