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GadgetUK · 05 June 2022, 11:31

Same problem here with two boards I built. I've tried the updated firmware today - this one wont boot it seems. No power light flashes or anything to provide a clue. I did make sure SJ4 and SJ3 were shorted to ground (as per this specific firmware - dont set those if you aren't using the firmware I am).

The RAM was exactly from the BOM (provided by Digikey). The CPLDs, I've swapped out too with known good ones from Farnell - same behaviour.

The behaviour with the release firmware was occasional yellow screen, quick power off and on and it would boot fine, but with no additional RAM.
DiagROM would always show no additional RAM on first boot, after 1st boot different amounts of RAM would be reported - often around 33MB (taking into account also the 16MB of SIMMS on the mobo).
1 out of maybe 20 or so cycles I did see the full 64MB + 16MB SIMMs appear in DiagROM, and the memory test passed at that point.

The FB100 wire is needed for the A3640 as well as A3660 - I wasn't aware of that initially. On the A3640, FB100 is underneath the PCB and I believe the pads are in different order to the A3660. I assume you are all using that wire, and if fitted to A3640, I assume solder to the LEFT pad, rather than the RIGHT pad when using A3660 PCB?

05 June 2022, 11:31	#25
GadgetUK Registered User Join Date: Mar 2013 Location: Manchester Posts: 189	Same problem here with two boards I built. I've tried the updated firmware today - this one wont boot it seems. No power light flashes or anything to provide a clue. I did make sure SJ4 and SJ3 were shorted to ground (as per this specific firmware - dont set those if you aren't using the firmware I am). The RAM was exactly from the BOM (provided by Digikey). The CPLDs, I've swapped out too with known good ones from Farnell - same behaviour. The behaviour with the release firmware was occasional yellow screen, quick power off and on and it would boot fine, but with no additional RAM. DiagROM would always show no additional RAM on first boot, after 1st boot different amounts of RAM would be reported - often around 33MB (taking into account also the 16MB of SIMMS on the mobo). 1 out of maybe 20 or so cycles I did see the full 64MB + 16MB SIMMs appear in DiagROM, and the memory test passed at that point. The FB100 wire is needed for the A3640 as well as A3660 - I wasn't aware of that initially. On the A3640, FB100 is underneath the PCB and I believe the pads are in different order to the A3660. I assume you are all using that wire, and if fitted to A3640, I assume solder to the LEFT pad, rather than the RIGHT pad when using A3660 PCB? Last edited by GadgetUK; 05 June 2022 at 11:41.