On 05/01/2021 12:22, Gerrit Heitsch wrote: > Unless you use the color clock or a multiple of it as dot clock, you > will have dot crawl. And if it's not a whole number multiple, you need > a PLL or another circuit that can accomplish the same. > Right, they changed the dot clock late and then added the PLL. Eventually the PLL got removed. It's kludge city. > Manufacturing issues aside, the chip designs were OK for back then. > And the fact and a lot of them still work more than 30 years later > does show their manufacturing quality wasn't too bad once they got the > process figured out. The industry is completely different now, they didn't have the tools back then etc etc. But that doesn't change just how amazing it is that anything from the commodore factory ever worked. Stringing capacitors onto lines that shouldn't have them etc is not a good sign :D > TED and 7501/8501 had problems if made in 1984. Versions made later > didn't die as easily. > Quite what they were doing making TED in 1987 is anyones guess... > Compared to what? Which other soundchip with the capabilities of the > 6581 existed back then? > Why does that matter? The first design isn't automatically good. > > They mostly did... Even the VDC got further revisions until it worked. > The working revisions didn't really ship enough to make up for it though. Very few people care about supporting the early NTSC VIC2's with the different timing, but if you write software to drive VDC then you have to care about every revision & the block copy/write workrounds are very annoying.Received on 2021-01-05 19:00:22
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