MTX 512 Black screen (of death?)

[JonB]

Not as useful as a Z80 ICE, but it can show timing information too. Also handles 68000 (with a different adapter box and clip).

Here's a random shot of some timing captures.

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It's very old and quite rare - there are no documents about it anywhere on the Internet, so you have to work out how to use it yourself. Fortunately it's reasonably logical. Mark will remember it from when I started repairing computers (there's a thread on StarDot about it - https://stardot.org.uk/forums/viewtopic.php?f=45&t=9732 ). Actually I think he might have one. Some fellow was selling them off a while ago, and I bought one to help the repair of my Philips P2000C luggable CP/M computer (which by the way is broken again).

[JonB]

It's a work of art inside.

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[Dave]

Lovely !

[JonB]

So.. we can see that the only lines that are working are A0-A5 judging by the pattern in the ROM dump. I got the probe out and found that pins 2 and 3 were not connected. Guess what?

That's right, I'd bent pins 1,2 and 3 when I put the ROMS back in after selling the Rememorizer. Pin 1 was making contact I think.

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What a Dibley.

It's all working now.

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Thanks for your help, Dave and Martin!

[Dave]

So, when you said . . .

No bent pins on the ROM chips.

Strictly speaking, I suppose you were almost correct

[Martin A]

oops

[JonB]

Now I can't go to Memofest 2021 as you lot will take the mick..

[Dave]

As if