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Hi Everyone,</div>
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As the local SDIYer I sometimes get asked to try and fix synths from the 80s like various Rolands, Korgs, Oberheims etc. and I generally just try to pinpoint the rough area of the issue and replace logic chips until the issue is resolved...</div>
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Most of these synths have a CPU connected to everything via a parallel address bus and a parallel data bus, with all sorts of glue logic chips doing various things. They also usually just have 1 DAC, time-domain multiplexed to all of the different parameters
via more logic chips. <br>
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Obviously this is very different to the modern ways that microcontrollers and DACs are used in synths, and since I wasn't around in the 80s, these older architectures are very foreign to me. To aid in my troubleshooting efforts, I would love to better understand
the details of how these architectures work, so I was wondering if anyone on here would be able to point me to any resources that could explain these types of systems to me, be they websites, articles, or books?</div>
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Thanks a lot for any advice you might have.<br>
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