PSU related Blitter issues (Atari STE)

[sascha.springer]

Thanks for your comments. I have changed the RAM modules but the glitches remained visible. The inserted modules have parity chips as well but I wanted to check out another fix before cutting traces. So actually I have replaced the CPU. The old type was an MC68000FN8 and the new one reads MC68HC000FN20.

I ran the demo for more than two hours and everything seems to be fine. I‘ll do another test tomorrow but I think and hope that this has fixed the issue.

[Steve]

Thanks for your comments. I have changed the RAM modules but the glitches remained visible. The inserted modules have parity chips as well but I wanted to check out another fix before cutting traces. So actually I have replaced the CPU. The old type was an MC68000FN8 and the new one reads MC68HC000FN20.

I ran the demo for more than two hours and everything seems to be fine. I‘ll do another test tomorrow but I think and hope that this has fixed the issue.

That is awesome news! Perhaps this new chip uses slightly less power or something.

[sascha.springer]

That is awesome news! Perhaps this new chip uses slightly less power or something.

Thanks.

I ran two more tests lately and everything works as expected. So finally I would say that the CPU change indeed fixed my issue.

[sascha.springer]

Here's a test version of the "Fast Bobs" demo for Blitter equipped Atari STs. Please let me know if there are issues on real hardware.

st_bobs.zip

(3.6 KiB) Downloaded 164 times

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[exxos]

So actually I have replaced the CPU. The old type was an MC68000FN8 and the new one reads MC68HC000FN20.

I ran the demo for more than two hours and everything seems to be fine. I‘ll do another test tomorrow but I think and hope that this has fixed the issue.

Sounds like a bus loading issue again, did you try changing the pull ups ?

[tzok]

Here's a test version of the "Fast Bobs" demo for Blitter equipped Atari STs. Please let me know if there are issues on real hardware.

It runs fine on my BLiTTER enabled 1040STfm.

[sascha.springer]

Sounds like a bus loading issue again, did you try changing the pull ups ?

At first I wanted to fix the issue with "plug and play" solutions before heating up my solder iron. So actually I did not add the pull ups.

It runs fine on my BLiTTER enabled 1040STfm.

Great! Thanks for the report.