Brett's STE - Repair thread

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rubber_jonnie
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Re: Brett's STE - Repair thread

Post by rubber_jonnie »

olivier.jan wrote: Wed Jan 26, 2022 10:32 am Sorry if this sounds stupid, but did you check the motherboard jumpers are set correctly for the type of ROM you’re using ?
Yep, one of the first things I did and verified the ROMs worked in my own STE with the same jumper settings.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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derkom
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Re: Brett's STE - Repair thread

Post by derkom »

FWIW, I toasted the GSTMCU on my STE (don't recall at this point how) and also had just a white screen and no diag cart boot. I got a new one from atarifreakz on evilbay. The replacement was surprisingly easy, considering I'm not super comfortable with my SMT skills. I used low temp solder to pull the old one off and then drag soldered the new one on, and it worked first try. (Not sure I would succeed again, though. Maybe I got lucky!)

So, if your diagnosis does end up pointing you to the GSTMCU, all is not lost!
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rubber_jonnie
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Re: Brett's STE - Repair thread

Post by rubber_jonnie »

derkom wrote: Wed Jan 26, 2022 10:43 am FWIW, I toasted the GSTMCU on my STE (don't recall at this point how) and also had just a white screen and no diag cart boot. I got a new one from atarifreakz on evilbay. The replacement was surprisingly easy, considering I'm not super comfortable with my SMT skills. I used low temp solder to pull the old one off and then drag soldered the new one on, and it worked first try. (Not sure I would succeed again, though. Maybe I got lucky!)

So, if your diagnosis does end up pointing you to the GSTMCU, all is not lost!
Cool, thanks, nice to know, but hoping it won't come to it!!
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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Re: Brett's STE - Repair thread

Post by rubber_jonnie »

Ok, so it seems that the Blitter issue was affecting things, I've done a new LA capture of all the ROM address lines plus /CE, and it seems that A1 and A2 are not playing nicely.

Screenshot 2022-01-26 at 12.00.33.png
Screenshot 2022-01-26 at 12.00.33.png (1003.12 KiB) Viewed 1156 times

A1 should go low 2us after the rest go low, so I will take a closer look at both A1 and A2 since neither are doing as expected.

A2 should go low at the same time as the rest.

Channel 0 is /CE, so that seems to be good again.

I can at least focus on those two and when they are working look at what's next.

I still potentially need to do what exxos and Stephen suggested, but this will do as a start.

If I can get both address lines to play nice and it still doesn't work, then I can look at the data lines.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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Re: Brett's STE - Repair thread

Post by stephen_usher »

So, now the search for the missing bits. :-)

Start at the CPU and go from there?
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
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rubber_jonnie
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Re: Brett's STE - Repair thread

Post by rubber_jonnie »

stephen_usher wrote: Wed Jan 26, 2022 12:54 pm So, now the search for the missing bits. :-)

Start at the CPU and go from there?
Yeah, I'm going to trace it through the schematics that Sporniket did, as if I keep it to just the top and bottom layers, I can trace every step of the way and make sure every last hop is good by buzzing them all out.

I'll look see everywhere they go, CPU included, to see what's what. At least it's narrowed down to just those 2 address lines for now.

I'll class this as progress :)
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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Re: Brett's STE - Repair thread

Post by stephen_usher »

Look closely, in case you can see the missing bits fall onto the carpet. ;-)
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
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rubber_jonnie
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Re: Brett's STE - Repair thread

Post by rubber_jonnie »

stephen_usher wrote: Wed Jan 26, 2022 1:48 pm Look closely, in case you can see the missing bits fall onto the carpet. ;-)
:dizzy:
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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Re: Brett's STE - Repair thread

Post by rubber_jonnie »

I can see the headline: "Squid like creature attacks Atari STE"

IMG_20220126_121133.jpg
IMG_20220126_121133.jpg (369.58 KiB) Viewed 1116 times
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
BrettRogersUK
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Re: Brett's STE - Repair thread

Post by BrettRogersUK »

I've enjoyed watching this journey. Really been an eye opener to see what can be done with the proper equipment. Look forward to seeing more! Looks like your making some progress at least looking at those pics from the LA.

Regards,

Brett
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