I've run into a few C64's that turned on "faster" than others, and it turns out some have a smaller cap in the reset circuit than others. I think the schematic says 10uF but many are larger than that (33uF?) causing the reset to be longer. I've not had a problem with the 10uF. -- Pete Rittwage https://c64preservation.com On Mon, Jan 25, 2021 at 03:09 PM, silverdr_at_wfmh.org.pl wrote: On 2021-01-25, at 20:58, groepaz_at_gmx.net (mailto:groepaz_at_gmx.net) wrote: Am Montag, 25. Januar 2021, 20:46:42 CET schrieb silverdr_at_wfmh.org.pl (mailto:silverdr@wfmh.org.pl): When testing BeamRacer prototypes on as many different C64 / SX64 boards as possible I remember encountering a problem with one machine, which we had to take into account and work around. The root issue with that particular board was that upon power-up the _RST (reset) line was not asserted for some prolonged time but became inactive (almost?) immediately once VCC stabilised. This didn't seem to affect the way the machine worked and I probably wouldn't notice it at all if it wasn't causing issues with our add-on. While now I am yet to find that particular machine back and analyse it thoroughly, I am wondering that's something, which could be described as a common failure or feature? Has any of you in the know encountered anything similar? sounds like a broken capacitor in the reset circuit :) It does sound like a hardware failure. I have to find that particular board back and check it thoroughly out. In the meantime I am interested in how common that might be. With the BR it was not critical - just unexpected. In the next project though, it would be hard to live with this. Obviously I don't feel like accounting for failed hardware but if that's something typical then I'd have to rethink. -- SD!Received on 2021-01-27 02:00:03
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