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    {
    >> add a WAIT procedure in your program to wait for the
    >> vertical retrace then your image will slide smoothly

    > I thought this was only a problem with CGA cards .. is that still
    > true?

    >> It's no longer a PROBLEM per se. It doesn't cause snow anymore, but you
    >> still get a jitter/flicker problem if you move an image
    >> without waiting for retrace. Problem is that the memory
    >> gets updated while the retrace is halfway down the

    > Where can I get source for such a wait procedure? Do you or JB? have
    > one?
    }
    var
     addr6845:word absolute $40:$63; {bios's crtc ptr}
      {CRT Controller=+0}
      {CRT Status=+6}
      {Mode Control=+4}

    procedure syncRetrace;assembler;asm
     mov ax,seg addr6845; mov es,ax;
     mov dx,es:[addr6845]; add dx,6; {find crt status reg}
     {@LOOP1: in al,dx; test al,8; jnz @LOOP1;}
     @LOOP2: in al,dx; test al,8; jz @LOOP2;
     end;
    {
    some people like to make sure the current retrace (if any) has ended before
    waiting for one to begin. I find it unnecessary in practice. But if you wanna
    do that, uncomment LOOP1.
    }

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