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PhilC
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Re: General Stuff(tm)

Post by PhilC »

That’s looking really good now Stephen, hopefully the keyboard won’t take too long to fix.
If it ain't broke, test it to Destruction.
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stephen_usher
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Re: General Stuff(tm)

Post by stephen_usher »

I'm hoping that replacing the Z80 SIO will do that as I don't know what else there is.

The CPU talks directly to the SIO and the SIO is getting power, clock and the data from the keyboard.
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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PhilC
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Re: General Stuff(tm)

Post by PhilC »

What's the chip type for the SIO? ~I may have some Z80 support chips here
If it ain't broke, test it to Destruction.
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stephen_usher
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Re: General Stuff(tm)

Post by stephen_usher »

I'll have to look for the part number more carefully, it just says Z80 SIO on the chip as far as I can remember.
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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stephen_usher
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Re: General Stuff(tm)

Post by stephen_usher »

It's a Z8440

After the machine had been working all afternoon I powered it off before dinner and then powered it back up after and it didn't boot.

Well, the one working floppy drive seems to have developed a problem with the head stepper motor or the motor drive circuitry. If it is able to seek it's only partially and it's incredibly noisy.

Thinking I may be able to use the original Drive A if I swapped over the spindle motor servo control board and... nope.

I think that the damp really got into the hardware on this machine, being stored in a damp, unheated outbuilding for about 30 years. I'm sure that more chips will start failing as they warm up and dry out.

Anyway, for the time being I think I'll just use the Gotek until I've sorted the keyboard out.

I'll put it back together again and let it sit until I get new parts later in the week.
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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PhilC
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Re: General Stuff(tm)

Post by PhilC »

@stephen_usher im sure I have some of those but I thought a Z8440 was a Z80 cPU as well.

Will check in the morning and let you know.
If it ain't broke, test it to Destruction.
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stephen_usher
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Re: General Stuff(tm)

Post by stephen_usher »

Looks like I bought the wrong chips, I didn't realise there were three variations. Doesn't really matter as the RxB is on the same pin, only TxB moves and I don't think it's used to talk to the keyboard.
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: General Stuff(tm)

Post by rubber_jonnie »

I've not yet watched this @stephen_usher but it might be worth a look: Kaypro IV up and running.
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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stephen_usher
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Re: General Stuff(tm)

Post by stephen_usher »

I saw that yesterday. His machine was fully working and he found and used the same floppy image that I found.
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: General Stuff(tm)

Post by rubber_jonnie »

stephen_usher wrote: Sun Feb 11, 2024 6:55 pm I saw that yesterday. His machine was fully working and he found and used the same floppy image that I found.
Ahh OK.

Are yours the 4 or the IV?
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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