ST536 STE EDITION

[exxos]

I volunteer some time to build an STE 536 and test it. I've built 3 or 4 ST536s. I've got some 288s in stock (will have to check the speeds), I've got the Xilinx toolchain
...
Let me know if you'd like another beta tester - I cannot promise to build it next week, but should be done before mid may.

The ST536 should work as it stands, but I will be changing to the 288 on those as well. I am using the 6ns chip, 10ns may work also, but difficult to say...

The STE536 boards as shown here will be in stock eventually.
viewtopic.php?p=124352#p124352

[exxos]

Not had much chance for much this week. The revisied PCBs are 99% completed at factory. I've somehow ended up fitting the 144's to them again :pullhair: :headbang:


Anyway, out with the old...


Step one – acquire target.

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Step two – lots of flux and low temperatures solder paste.

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Step three - around and around we go like record playing right round round round, with the gas soldering iron..

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Step four - More flux and low temperatures solder paste

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Step five – go around all the pads to make sure they are tinned with the low-temperature paste and then admired the carnage.

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Step six - cleanup with IPA wipes and inspect for damage, where the looks to be non-thankfully :)

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That's enough stress for one day! :lol:

[JezC]

Looking good there @exxos!

If that STE with the new CPU and 4MB RAM upgrade is stable, it might be a candidate for one of these... :)

I'd better start saving up...

[exxos]

If that STE with the new CPU and 4MB RAM upgrade is stable, it might be a candidate for one of these... :)

They were stable on my machine but nobody else's :lol: :roll: Then I fixed it for others and it stopped working on mine :lol:

The larger PLD will rule out a lot of issues and give me more freedom to tweak stuff.

[JezC]

If that STE with the new CPU and 4MB RAM upgrade is stable, it might be a candidate for one of these... :)

They were stable on my machine but nobody else's :lol: :roll: Then I fixed it for others and it stopped working on mine :lol:

The larger PLD will rule out a lot of issues and give me more freedom to tweak stuff.

Well, if this one works, that should give me at least 3 (possibly 4) working STEs to test on if you need a wider sample set to test with? :D

[exxos]

Well, if this one works, that should give me at least 3 (possibly 4) working STEs to test on if you need a wider sample set to test with? :D

Yeah. @Badwolf suggested "passing to the left" as a test run. So when I get one working, I'll pass it to the next person to test... Then pass it onto the next. It be a bit time consuming but it may be the only way to see if any boards are more sulky than others.

I know I had issues with my V1 STE booster as the external blitter machines had slightly different behaviour than the internal ones.

I've got a few STEs here I can test but they all broken and need fixing :( mostly need new simm sockets and reset switches.. it's finding the time to do all this stuff which is the problem.

[JezC]

Yeah. @Badwolf suggested "passing to the left" as a test run. So when I get one working, I'll pass it to the next person to test... Then pass it onto the next. It be a bit time consuming but it may be the only way to see if any boards are more sulky than others.

I know I had issues with my V1 STE booster as the external blitter machines had slightly different behaviour than the internal ones.

I've got a few STEs here I can test but they all broken and need fixing :( mostly need new simm sockets and reset switches.. it's finding the time to do all this stuff which is the problem.

Good idea - one of mine has an external blitter, the others are all internal blitter. Big issue for the other STE boosters is that most of them don't have the F257 fitted (one does that I know of, might need to check the one on memory soak test as well...just in case).

I do have one needing new SIMM slots (but IIRC I got a SIPP upgrade pack so I can fit them once and hopefully then have fewer potential problems in the future).

One thing at a time though! Yeah, right....
:roll: :lol:

[exxos]

Good idea - one of mine has an external blitter, the others are all internal blitter. Big issue for the other STE boosters is that most of them don't have the F257 fitted (one does that I know of, might need to check the one on memory soak test as well...just in case).

It's a valid point about the 257. My V1 STE booster needs the better chip as it's driving the 32Mhz clock... The TF536 based booster use their own clock... So it shouldn't matter... But it's possible it could be a factor....

My current test machine uses the F257... I wonder what others use @PhilC @Badwolf @coonsgm @Steve

[PhilC]

This is the board I am using.

PXL_20250427_130840936.jpg

U505 is a 74F257, U500 & 501 are 74F374 but the rest are all LS spec.

Will do latest no TT ram test shortly

[PhilC]

Quick update,

I've just tried the no TT ram firmware and it still gets a stuck trying to boot ST536 tos but does boot to desktop now with EmuTos 1.2.1 and will see and format a floppy without issue.

ST,536 tos gets stuck here

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