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Re: Mega ST project
Posted: 15 Dec 2021 14:33
by frank.lukas
Bei der alten Platinenversion (PAK/3-030) müssen noch einige Leitungen gefädelt werden, da das Layout nur die Versorgung des GALs mit Vcc und GND vorsieht. Die neue Platinenversion (PAK/3-030A) enthält alle nötigen Verbindungen, aber mit einem anderen Pinout!
It say the old pcb has only VCC and GND connected to the GAL U3. You must see the schematics from the PAK ...
PAK68/3-020 40Mhz
Posted: 15 Dec 2021 16:45
by frank.lukas
PAK.pdf
U3 = puk.jed and not puk_a.jed !
pak_puk.png
Re: Mega ST project
Posted: 15 Dec 2021 18:17
by Darklord
If it helps, here is the English version of the Pak PDF:
PAK_en.pdf
Re: Mega ST project
Posted: 16 Dec 2021 07:59
by HigashiJun
@frank.lukas @Darklord
Thank you both for your feedback.
I have the English version of the manual, so no worries.
The GAL is the "P3-PUK", so no problem here too.
I thought I had the patch Frank is talking about done on my PAK68, but I have realized the bodge wires are just another patch (see the picture below):
PAK1.jpeg
So I will have to add my thin gauge wire to make the 68000 work.
Hope to have some free time this week-end...
Re: Mega ST project
Posted: 16 Dec 2021 16:24
by Darklord
All of this makes me glad that I wound up with the later version of the Pak board.
It's very interesting to watch you work through these problems. I'm sure they will
submit to your and Franks' technological prowess, in the end! :)
Re: Mega ST project
Posted: 16 Dec 2021 17:50
by Wolfgang
frank.lukas wrote: 15 Dec 2021 11:40
I ask Idek for a 030 STGA T8 nova driver ...
And here they are. Totally untested since I don't have this setup. But I doubt that it is driver related anyway. The 68000 drivers should also work.
Re: Mega ST project
Posted: 16 Dec 2021 21:06
by HigashiJun
Thank you !
I will give them a try anyway.
:)
Re: Mega ST project
Posted: 17 Dec 2021 12:05
by HigashiJun
Ok, one issue is solved. :D
The PAK68 now works with a CPU on top of it, so the fallback mode is operational.
As Frank Lukas wrote, the wire patch at the bottom of the board was missing.
Now, it is applied:
PAKpatched.jpeg
Remains the FDD issue...
Re: Mega ST project
Posted: 17 Dec 2021 12:38
by HigashiJun
Some more feedback after some quick tests:
- When the PAK is fitted on the CPU relocator, I get RAM errors on the Atari boot screen.
- Fitted directly on the motherboard, no more RAM errors occur.
- The fallback mode does not work with the MC68HC000 CPU and the PAK simply does not boot with this CPU, even in PAK mode.
- Works great with a MC68000 CPU (fallback mode and PAK mode).
- The FDD works in fallback mode (8 Mhz).
- I have no more error message while accessing the FDD in PAK mode, but only a reboot.
That is all for now...
Re: Mega ST project
Posted: 17 Dec 2021 13:01
by frank.lukas
pm pakman and ask for tips ...