New project: An ACT Apricot F1 "barn find"

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stephen_usher
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Re: New project: An ACT Apricot F1 "barn find"

Post by stephen_usher » Sun Sep 12, 2021 6:42 pm

If you can make it then it'd be great to meet you.
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: New project: An ACT Apricot F1 "barn find"

Post by rubber_jonnie » Mon Sep 13, 2021 12:03 am

stephen_usher wrote:
Sun Sep 12, 2021 6:42 pm
If you can make it then it'd be great to meet you.
I'll see what I can do :)
Collector of old Atari things:
800XL + Ultimate 1MB, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k +APE Warp) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg), 1040STF long button floppy, 2x 1040 STFMs + Gotek, 2x 4160STE with 32Mhz booster, ROM switcher, Mega ST1, Mega ST4, not to mention various bare ST boards for testing including a PAK 68/2 :)
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk

stephen_usher
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Re: New project: An ACT Apricot F1 "barn find"

Post by stephen_usher » Mon Sep 13, 2021 1:03 pm

The memory upgrade PCBs have arrived.

IMG_2380.jpg
IMG_2380.jpg (378.77 KiB) Viewed 165 times

The hardest thing I need to do is solder SIOC surface mount SRAM on the other side, which has incredibly fine pins!
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: New project: An ACT Apricot F1 "barn find"

Post by rubber_jonnie » Mon Sep 13, 2021 3:01 pm

stephen_usher wrote:
Mon Sep 13, 2021 1:03 pm
The memory upgrade PCBs have arrived.
IMG_2380.jpg
The hardest thing I need to do is solder SIOC surface mount SRAM on the other side, which has incredibly fine pins!
Very nice :)
Collector of old Atari things:
800XL + Ultimate 1MB, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k +APE Warp) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg), 1040STF long button floppy, 2x 1040 STFMs + Gotek, 2x 4160STE with 32Mhz booster, ROM switcher, Mega ST1, Mega ST4, not to mention various bare ST boards for testing including a PAK 68/2 :)
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk

stephen_usher
Posts: 2062
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: New project: An ACT Apricot F1 "barn find"

Post by stephen_usher » Mon Sep 13, 2021 7:02 pm

The board passes its initial electrical and physical tests.

I fitted a connector to an unpopulated board to do a sanity check. It fits correctly, +5V and GND are in the correct places and the machine still boots, which is a bonus. I've not checked any of the data or address lines yet but it's a good start.

IMG_2381.jpg
IMG_2381.jpg (72.42 KiB) Viewed 146 times

I also tried the 8 pin DIN socket but that's not so good news. The pins are FAR larger than the holes I specified. I'm going to have to file the pins down for these boards and modify the footprint design.
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.

stephen_usher
Posts: 2062
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: New project: An ACT Apricot F1 "barn find"

Post by stephen_usher » Mon Sep 13, 2021 8:49 pm

Fitted everything except for the GAL and memory and everything seems to be operating correctly.

The address lines are latching, the control lines are doing what seems to be correct and, more importantly, no magic smoke. The machine still boots normally.
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.

stephen_usher
Posts: 2062
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: New project: An ACT Apricot F1 "barn find"

Post by stephen_usher » Mon Sep 13, 2021 9:56 pm

GAL programmed and installed.

I'm going to need a bodge wire as the GAL programming software doesn't like a logic high output on pin 19 so I've had to switch to pin 15.

Still, I'm seeing activity on the selection line during the initial RAM test stage of the ROM along with data line activity at the same time.

So, bodge wire and SRAM (eek!) to do tomorrow evening.
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.

stephen_usher
Posts: 2062
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: New project: An ACT Apricot F1 "barn find"

Post by stephen_usher » Mon Sep 13, 2021 10:22 pm

This is the scary surface mount device pad...

IMG_2383.jpg
IMG_2383.jpg (39.67 KiB) Viewed 129 times

Still, the board looks OK in general. The noise levels on the traces are fine, so a 4 layer board is not needed.

IMG_2382.jpg
IMG_2382.jpg (92.11 KiB) Viewed 129 times
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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JezC
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Re: New project: An ACT Apricot F1 "barn find"

Post by JezC » Mon Sep 13, 2021 10:29 pm

@stephen_usher That's a similar footprint to all the parallel Flash devices we're using on our products...as/when we can get hold of them!

Our repairs guys can swap the chips off one board & onto another in mere minutes with almost no problems...I'm never likely to get anywhere near their levels of expertise!

Good luck when you attempt to solder that one...and stay off the coffee for a couple of hours beforehand ;)

stephen_usher
Posts: 2062
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
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Re: New project: An ACT Apricot F1 "barn find"

Post by stephen_usher » Mon Sep 13, 2021 10:43 pm

Hehe. Yeah! It's going to be "fun"!
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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