Hey guys,
Just hoping for some pointers on this. At first I thought it was a RAM issue but the memory test passes fine on diagnostics and on YAART. Machine is an old rev B ST. Any ideas? Thanks
Black vertical lines on ST
Re: Black vertical lines on ST
I recently helped solve a similar issue: https://www.atari-forum.com/viewtopic.p ... 63#p421063. (Of course, in your case it won't be exactly D10, but another data line.)
Re: Black vertical lines on ST
Thanks @czietz I'll check it out!
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Re: Black vertical lines on ST
Looks like a Shifter issue.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
Re: Black vertical lines on ST
PS: Looking at the pattern on your photo, I suspect D3.
Re: Black vertical lines on ST
Machine would not boot like that if it was a RAM fault, you basically have one data bit low all the time. I would check out the databus to the shifter or re-solder it etc.
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
Re: Black vertical lines on ST
@Steve That makes sense considering the other stuff we found.
If it ain't broke, test it to Destruction.
Re: Black vertical lines on ST
Hi guys,
I've checked D0 to D15 going to U22/26/23/27 pins, everything seems to be connected fine (buzzed them all) I also swapped out all chips U22/26/23/27 with different ones. I also swapped the shifter, still the same.. hmm what am I doing wrong?!
Here's a picture of the lines I've buzzed (highlighted in green spray paint) they all seem fine:
I've checked D0 to D15 going to U22/26/23/27 pins, everything seems to be connected fine (buzzed them all) I also swapped out all chips U22/26/23/27 with different ones. I also swapped the shifter, still the same.. hmm what am I doing wrong?!
Here's a picture of the lines I've buzzed (highlighted in green spray paint) they all seem fine:
Re: Black vertical lines on ST
@Steve ok so all the lines buzz out ok, good. Now stick your scope on them one by one and one of them is likely staying low, hence the black line.
If it ain't broke, test it to Destruction.
Re: Black vertical lines on ST
Check other side of U22, U23, U26, U27.