On 2013-12-14, at 21:49, Jim Brain <brain@jbrain.com> wrote: >> I see. I am not sure what the problem is and if it has anything to do with the 3V3 but EasyFlash3 doesn’t really work when plugged into SX-64. I asked skoe about it but he probably didn’t find time to investigate it yet. > > Not sure a lot of investigation is needed there. The ribbon cable on the expansion port of the SX64 ruins all the signals, Really? I didn’t think us to be in such frequency range here so that it would matter that much. > and EasyFlash and a lot of the newer cart options (Chameleon, 1541U, etc.) won't work when doing things that require tight timing. If you could turn the EF3 KERNAL replacement function off, I bet the EF portion would work, and 1541U no doubt works as long as the function you are requesting does not require tight timing. I don’t have the Chameleon (tried to put my hands on one for some time) but 1541U-II works well in the very same machine. I mean the KERNAL replacement function, which is the most timing critical AFAIU. > It's the cable, pretty much. I bet if you pulled the case, and ordered a shielded ribbon cable (or better, created a non ribbon cable option), the problem would disappear. Pardon the ignorance but what’s so wrong with the ribbon at the frequencies we deal here with? Or - generally - with the ribbon. How much it differs from e. g. traces running parallel across the big C64 PCB? What with the (even longer) ribbon used for the USER PORT in SX-64? Right, I know of a problem when one friendly dude installing my DD3 board in a 1541-C ran the CPU ribbon (all clocks/buses) closely over the Hybrid IC there. He’s got all kind of read errors and other strange behaviour. Shielding the ribbon with a copper foil placed between it and the hybrid cured the problem. But I believe this was the digital noise disrupting analogue operations, rather than the other way around.. At least that’s what I believe it to be. >> Anyway nice to see that you successfully entered the CPLD zone. Good luck, Jim. >> >> P. S. Please keep at least in the back of your head the atapi stuff we talked about ;-) > > Yes, I have it here :-) GREAT! :-D -- SD! Message was sent through the cbm-hackers mailing listReceived on 2013-12-15 13:00:03
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