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Re: PAL card: I think I've got it but...



Wayne Stewart wrote:


One more thing, would it hurt if I feed the video signal into the DMA
chain? What in H*ll is this chain actually supposed to do? Do any
peripheral cards in fact use it?


You're talking about pins 24 & 27, right? Doesn't seem to see a lot of
use in the II+. I took a quick look at a few cards that were handy and
the only ones that used it were the ROM card, the superdrive card and
some Z80 cards. Could likely find quite a few more if I really started
digging. Quite a number of cards for the IIe did use it but I wasn't
counting those.

Actually I meant pins 23 & 28. Those seem to see even less use. Almost all cards connect them straight through.

What's the protocoll for those "chains" anyway? They only connect the cards to each other, not to any other thing on the motherboard. If they're used for arbitration, wouldn't they stop working when even one slot is empty?

--

Linards Ticmanis

 The Master said, "The business of laying on the colors follows the
preparation of the plain ground."