Posted By
TLC
on 2009-09-10
17:31:07
|  Re: SID-card scheme?
There might be some confusion here. Here: Yellow Pages #1 which is dated 1992.08.21 Proky states that Csory's card needed a re-design of the clock divisor, and (which appears more important) by then he actually had a working SID-card provided by Christian Schäffner (Solder). He gives details about the base addresses of both cards ($fd40 and $fe80). He mentions that the card he had needed the CPU clock to be halved ($ff13 bit 1, disable double clock mode) and that the card sometimes misses some voices etc. (which should have actually been a side-effect of the method he's describing later, about how he plays SID tunes on the card... ie. by copying SID register values from the $d400 map frame by frame instead of redirecting the player to the new base address, so it's not some hardware issue, after all). I'm really confused about these new findings... Solder's SID card is known to work well with no extra conditions concerning clocks, and he claims to have had the cards ready by 1992 (as to what month and week that means I don't know... my card is like this one: Solder's SID Card (Older), and it's already not from the first production run as that one had a PAL as address decoder, not a GAL). If Proky really had a card produced by Solder, that must have been an early prototype version. Also, if the date is correct, then I must have met him late 1992, probably in Szeged (I still can't remember if I really did attend that party, but I probably did) else I could have not seen him together with a prototype SID card version. ...But if Proky had a card whose clocking scheme was still in development, and probably a prototype version, and by then Csory had already promised to produce a card whose clocking was correct (and Proky. consequently, didn't have Csory's prototype version), then I must have seen Solder's prototype card, not the one by Csory.
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