exxos's Atari, Amiga & retro forum

@rubber_jonnie cool that you've got it all running now, thanks to a duff reading on A2.

PhilC wrote: 24 Sep 2026 11:32 @rubber_jonnie cool that you've got it all running now, thanks to a duff reading on A2.

I'm a bit annoyed I didn't pick it up sooner, but I do have a habit of going back across old ground and I think it's a good job I do.

Thank god for the oscilloscope!!!

rubber_jonnie wrote: 24 Sep 2026 11:36

PhilC wrote: 24 Sep 2026 11:32 @rubber_jonnie cool that you've got it all running now, thanks to a duff reading on A2.

I'm a bit annoyed I didn't pick it up sooner, but I do have a habit of going back across old ground and I think it's a good job I do.

Thank god for the oscilloscope!!!

I had similar with a pull-up on a Mega ST board once, took me half a dozen times to spot it, so know what it feels like.

PhilC wrote: 24 Sep 2026 11:38

rubber_jonnie wrote: 24 Sep 2026 11:36

I'm a bit annoyed I didn't pick it up sooner, but I do have a habit of going back across old ground and I think it's a good job I do.

Thank god for the oscilloscope!!!

I had similar with a pull-up on a Mega ST board once, took me half a dozen times to spot it, so know what it feels like.

Yeah, I had a similar issue with a Mega as well, one of the resistor packs was cracked. Interestingly since I reflowed the A2 connection on Dave, it no longer needs the pull up.

If I just boot up the RAM passes, however if I do the advance test it fails. I think it's likely OK though, but I may order another RAM IC for peace of mind.

OK, gratuitous shot of the final install of the RAM board.


I ultimately made a plug for the smaller expansion header and soldered the leads directly to the mainboard with a hint of hot glue for strain relief.

All working fine, so I need to get the machine reassembled now and properly test.