More talk about 16×8 sprite cell mode…

There original premise here.

Have a look at this screen grab here.

This is Chris’ screen test rom. I have it running on an original white PCE with the tototek card. The BG is in normal res, but the sprites (the little red markers) are half res. Now, this is better than what I expected. Because, if I’m correct, this won’t generate two hsync’s per scanline. Also, the border on the right is minimal. My capture card picks up the whole overscan, so that somewhat wide border is actually about 8 pixels for a normal screen – which is much better than my other method/idea/expectations.

There still needs to be some more tests, but this is pretty exciting. Mostly because of the small border, but largely still because the BG is uneffected. This also gives a little insight in how the VDC processes things internally. From the looks of things, sprites for the coming up scanline are figured out in advance to the BG. To get the VDC to do this, you need *very* specific horizontal timing settings, but I’ve been able to do it in all resolutions. I’m excited to say the least. Next thing to do is test the sprite per scanline bandwidth and see how bad it’s been effected 😉


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