REV 3 - REV 5 - The beginning (ST536)

[exxos]

Those two pins are shorted, just measured.

Great, that is exactly what we were looking for. With A24 shorted to GND, the PLD never sees it go high, so the TT-RAM at $01000000 and up looks like ST RAM, and TOS decides there is no TT-RAM.

Clear the bridge between pins 113 and 114 with some flux and solder wick, then measure again to make sure the short has gone. If it still reads as shorted after that, the bridge may be under the pins or somewhere else on that track, so let me know. Worth double checking with a magnifier around every bend to make sure there are no other nasty surprises anywhere...

Once it is clear, power on and you should see the TT-RAM test bar on boot. TTCHECK test 1 should then say it passes, _ramtop should no longer be zero, and test 3 will be skipped as TOS is then using the TT-RAM.

[exxos]

Success

Excellent, glad that sorted it! So it was a solder bridge between A24 and GND on the PLD. If you run TTCHECK again, test 1 should now pass and _ramtop should show the TT-RAM size. Nothing beats the feeling of a machine finally finding all its memory, like the day you plugged in your first 512K upgrade

[Badwolf]

And no, a fast ROM is not needed either. Fast ROM on the ST536 has nothing to do with the speed of the ROM chips. TOS is copied into TT-RAM and runs from there, so ordinary ROMs are fine, there is no need for 55ns parts like older designs used.

OK, that's cool.

As for the LLM comment, I find that frankly insulting. I did not ask an AI to write a reply for me. I wrote every response myself and used AI to reword it, and I have now spent over three hours typing out replies to you. I know you are against AI, but I simply do not have the time to check every typo and line up everything I say without it. Calling it my LLM's post just brushes aside everything I said without answering any of it.

I haven't referred to any of your replies to me as LLM posts. I used it to identify this one:- viewtopic.php?t=3992&start=1100#p147905

I'm not against LLMs in general. I use one occasionally. I am against them being used for things for which they aren't suited and am in general against the way many have pirated material in their training, but in this case I was only using it to identify the post to which I was referring. Which was none of your replies to me.

If that post was not written by an LLM, then I apologise.

BW

[coonsgm]

That felt good, but now for the next bug when running Frontbench I get "TOS Error 35"

Gembench makes it through some parts then throws the following

IMG_5297.jpeg (49.9 KiB) Viewed 19 times

[exxos]

That felt good, but now for the next bug when running Frontbench I get "TOS Error 35"

Gembench makes it through some parts then throws the following

Good news on the TT-RAM, but those errors could mean the TT-RAM is still not quite right. Could you run YAARTTT first, to make sure the TT-RAM is trouble free before running any other software, and post what it reports?

Also, were Frontbench and GB6 running in TT-RAM, i.e. have the program flags been set to load into TT-RAM?

Can you run tests one at a time (click on tests one at a time) in GB6 and see if any test repeatedly fails or is just a general failure.

[coonsgm]

Both programs are set to run from TT-RAM.

Clicking on tests one at a time, the failure happens seemingly randomly (I know it isn't random) displays that error or forces a reboot.

I've had multiple instances where each test individually has passed, but then randomly the system reboots or a test is failed. Alt-RAM test has passed individually as well.

[exxos]

Both programs are set to run from TT-RAM.

Clicking on tests one at a time, the failure happens seemingly randomly (I know it isn't random) displays that error or forces a reboot.

I've had multiple instances where each test individually has passed, but then randomly the system reboots or a test is failed. Alt-RAM test has passed individually as well.

Thanks. Random failures like that usually point to something intermittent, so let's narrow it down first.

1. Please run YAARTTT, which you can find here: viewtopic.php?t=28
Leave it running in a loop for a good while rather than a single pass, as intermittent faults often take a while to show up, and post what it reports.

2. Clear the TT-RAM load flags on Frontbench and GB6 so they run from ST RAM instead, and see if they are still unstable.

3. Give the area around the PLD a good clean with isopropyl alcohol to remove any flux left over from fixing the bridge, and have another close look over the PLD and SDRAM pins while you are there.

If it is fine from ST RAM but not from TT-RAM, then we know it is somewhere in the TT-RAM side. If it still crashes from ST RAM, then it is something else entirely.