exxos blog - random goings on

[exxos]

I have un-forgotten about the DAC FIX PCB again. I designed a slightly smaller board a couple years ago but could not get then assembled as they were too small for JLC to do them But by some "miracle", They can assemble down to 10x10mm now

So now the new board is in my basket awaiting production.

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I will see if I can a few of the Falcon FPU osc clock boards done next...

[exxos]

FPU OC PCB done. JLC parts placement preview is out as normal.

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Going to have to take a few days off from stuff again because, as usual, the hurting hands thing

[Badwolf]

FPU OC PCB done. JLC parts placement preview is out as normal.

Dunno what you're on about -- looks exactly like the way I place 'em!

BW

[exxos]

Dunno what you're on about -- looks exactly like the way I place 'em!

[exxos]

Scored this off evilbay. Did not really expect it to work though anyway. The listing was stated as for parts not working, so I guess that was a bit of a clue Currently just seems to be a crash screen generator I took the chips out and cleaned them up a bit as there is basically corrosion everywhere.

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Decided just to chuck it in the ultrasonic... Only did not quite fit in the basket

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I doubt this will cure the poorly thing. I just wanted to clean a motherboard to see what happened more than anything

[exxos]

Holy mother of dirty motherboards Batman!

The text has vanished off half the chips as well

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[sporniket]

so shiny after a bath

[exxos]

so first up, it seems to have some weird reset issue. Occasionally it would boot up..

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I found C100 is basically limiting the reset voltage to just 1 volt! so for a quick fix I just slapped another over the pull-up and to actually reset properly!

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The next problem is, it seems to be suffering from that "Shifter goes nuts" problem.

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On this machine it does not seem to matter which version of the video shifter is fitted.

In any case I managed to get it run long enough to run a pass of GB6.

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It is indeed a very poorly STE. With a lot of TLC I think it can be brought up to fully functional. Though I will probably used as a guinea pig for 16Mhz buffer tests when/if I get time.

[exxos]

How time flies..

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[exxos]

I was not at home yesterday so the STE is turned off the entire time. Only thing I did just was to change the reset caps to solve the previous issue. And now with either version of shifter installed the video is perfectly fine again.

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