On 10/08/2012 09:15 PM, email@example.com wrote: > > On 2012-10-08, at 21:07, firstname.lastname@example.org wrote: >>> >>> Could you upload a picture of the circuit as used? >> >> PCB: >> ===== >> http://dl.dropbox.com/u/58002657/cbm/c64/Scan-121008-0001.jpg >> http://dl.dropbox.com/u/58002657/cbm/c64/Scan-121008-0002.jpg >> >> On board and worn out with tens of rounds of de/re-soldering.. (full res - above 1MiB): >> ======================================================================================= >> http://dl.dropbox.com/u/58002657/cbm/c64/2012-10-08%2020.48.02.jpg >> http://dl.dropbox.com/u/58002657/cbm/c64/2012-10-08%2020.48.19.jpg > > Just in case you'd wonder.. the PCB doesn't show the last gate of LS11 tied to GND, neither VPP of the EPROM to VCC. Those I added on the assembled adapter manually. As you know by now, I wondered... Also, I noticed that the trace for +5V to the LS11 is a bit on the long and winded side. I doubt that it makes a difference, but could you add a direct wire from pin 28 of the EPROM? The next step, if this fails would be to take out the 74LS00 and bridge the signals so that you only have 1 char set and see if that makes a difference. (Take out the 74LS00 and put a bridge between pin 6 and pin 2 of the now empty socket, assuming your schematic matches the PCB) Gerrit Message was sent through the cbm-hackers mailing listReceived on 2012-10-08 20:01:06
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