Re: Video Coprocessor
On Mon, 10 Nov 1997, KC5TJA wrote:
> > What is a "spurious black line" I have no idea, but I belive that this
> > might happen.
>
> A spurious black line occurs when the CPU has higher priority than the
> video refresh hardware (however it may be implemented). This means the
> video serializer register shifts all its pixels out before it can fetch
> the next word of the video stream. In short, you get a small black line
> in the middle of the video stream. Hence it's name... :) The earlier CGA
> and EGA hardware for the PCs also exhibited this problem. This was fixed
> in later generations of the EGA. Fortunately, VGA never had the problem
> to begin with.
In MuP21 VP just repeats the pixels it had in SR (or so I'm being told),
making the previous line 4 pixels longer.
--
Penio Penev <Penev@pisa.Rockefeller.edu> 1-212-327-7423
