Timothy Miller wrote:
On 8/9/06, James Richard Tyrer <[EMAIL PROTECTED]> wrote:


Well that is another issue isn't it.  VGA is based on NTSC.  How is it
displayed on PAL?

Do we care?  We'll just put out a valid PAL mode and use 400 of the
scanlines (interlaced) for the image.

That will certainly work for the character mode boot. My comment was a bit OT.

But, I was wondering about the general issue. If a user tries to display VGA on a PAL TV set, what happens. Scan conversion would fix the problem but IIUC we aren't going to use hardware scan conversion. This would be another advantage of trying to leverage existing hardware.

Obviously, it would be best if the user chose a pixel format (768 x 576) that was suitable for PAL display.

I also wonder (I do that and > 90% of the time it goes nowhere, but occasionally I come up with something) if PAL TV sets will run at 60 Hz vertical field rate? If so, they would probably be able to display VGA since the horizontal (interlaced) scan rates are about the same (15625 vs. 15750).

--
JRT
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