exxos's Atari, Amiga & retro forum

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.

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

PhilC wrote: 02 Sep 2022 23:14 @kodak80 I was going to make some of those but you beat me to it :D

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

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.

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

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:


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:

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?

Is that your first board, Rob?

PhilC wrote: 10 Nov 2022 17:15 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.

atari030 wrote: 10 Nov 2022 22:20 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.

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.

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

Diag cart works


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


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.