kodak80 blog

[kodak80]

For my ST ATX board which is now cased in a black Micro ATX case I have ordered these VGA to IDC boards to allow me to used a 16 pin ribbon cable to mount the VGA port somewhere.

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VGA to IDC16 adapter gerber.zip

(17.64 KiB) Downloaded 72 times

[PhilC]

@kodak80 I was going to make some of those but you beat me to it

[kodak80]

@kodak80 I was going to make some of those but you beat me to it

Cool. I can also confirm that the VGA 16 pin header works fine. I tested it today.

Still need to test parallel and serial headers.

For the dual TOS, I am using 1.04 with IDE patch and 2.06. 1.04 boots the IDE CF card fine.

[atari030]

This is damned exciting. Did you come up with a way to hook up an Atari KB?

[kodak80]

I have 1 working ST ATX system at the moment but I am thinking that the pull-up resistors on it need to be changed on the next board I am building.

The ST ATX system is currently using 10K/4.7K pull-up resistors and I note on the H4/H5 we used 2.2K/1K pull-up resistors.

ST ATX BUS PULLL_UPS:

Bus Pull-ups ST ATX.jpg (61.55 KiB) Viewed 2208 times

I tried adding a 64 pin expander board onto my existing ST ATX system to relocate the CPU and add a 2nd 64 pin socket but this caused my IDE disk to get corrupted. I have removed the expander and tings are stable again with the IDE CF drive.

On the next board, I have decided to socket the SIL resistors although there are still 3 SMD resistors (R44, R45, R46) to consider:

Board 3 SILs socketed.jpg (210.37 KiB) Viewed 2202 times

[PhilC]

Hi @kodak80 I've finished my ATX board but have a number of issues with it that I've not worked out yet.

I get bad ghosting on the display, Tos 2.06 fails the memory test after 8 dashes and the floppy doesn't work.

I wondered if there was any fixes that need applying to a standard V1.1 board other than the ISA one?

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[atari030]

Is that your first board, Rob?

[kodak80]

Hi @kodak80 I've finished my ATX board but have a number of issues with it that I've not worked out yet.

I get bad ghosting on the display, Tos 2.06 fails the memory test after 8 dashes and the floppy doesn't work.

I wondered if there was any fixes that need applying to a standard V1.1 board other than the ISA one?

C6D569B0-5227-4F8E-8B81-65C718D729AC.jpeg

No, the only fix is for the ISA slot. There are 2 jumpers for switching TOS versions. One switches the TOS loaded from the ROMs and the other jumper is to switch on/off 256k decoding. Both jumpers need switching if you have TOS 2.06 / 1.04 in the ROMs. A GAL/PAL IC11 has the IDE and TOS decoding so you could also check this is programmed correctly. Does TOS 1.04 load without issues?

I also use 1.04 with the IDE patching applied so the IDE boots from both TOS 2.06 and 1.04.

[kodak80]

Is that your first board, Rob?

I am now on my third working board. The third one has the SILs in headers so I can test the CPU expander and test PC-Speed etc. I am currently using the original SIL resistors in the BOM for the ATX board.

[kodak80]

As shared on other forums. My ISA Cartridge adapter works fine with bodge wires from underneath the GLUE IC (pins 17 & 18) for ROM3 & ROM4.

Cart Adapter-routed_2022-09-08.zip

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Cartridge slot fits flush with the external ATX case so will not allow cartridges in cases to be fitted. I am working on the next version of the adapter with the cartridge slot sitting outside the ATX casing...


Cubase 3.0 re-created dongle works

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Diag cart works

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DoG's MV16 cartridge works. Worlds first Atari ST ISA sound card...

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IDC 26 pin connectors for Parallel and Serial need a fix board to correct the output when using standard IDC to DSub connectors. I tested the IDC PCB fix by printing to an old dot matrix printer.

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26 pin Header Fix gerber 2.54mm.zip

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