PLD Plague – Problem Solved!

The G80-S has been plagued by the simplicity of it’s design.  The use of a single PLD to do all of the onboard decoding has led to an unusual issue.  One where the Programmer of choice is apparently selective concerning which PLDs it decides to program.

Thats right, it appears that the MiniPro Programmer just doesn’t like GAL22V10 PLDs.  I do not know why.  All I know is that some variants work without any issue. Some will not program at all.  While others have intermittent programming problems.  The interesting part is that I have not experienced this with any variants of the GAL16V8.

The solution to this issue has been to build a new programmer.  Luckily for me, there was a gentleman in Japan who took this task upon himself almost 20 years ago and created the ELM programmer and accompanying software.  See that information here:  ELM Gal Programmer.

Some time back there was another gentleman with the N8VEM project that decided to take the ELM programmer’s schematic, and create a PCB.  And then some time later I found the project and ordered a batch of boards.  And as a result of that brief history, I can now program GAL22V10s of any variety (not Atmel parts) with only some small modifications to the WinCUPL JEDECs (The software appears to not like all of the documentation in the JEDEC files).

The software requires a DOS computer with a parallel port.  Here I am using my Halikan LA-5040, a portable 386 machine with 5mb of memory and a monochrome LCD (or VGA out).  Here you can see the dump of the contents of one of the G80-S Micro’s PLDs.  It works!

So what does this mean, you ask?  Well, it means that we can finally start stocking the G80-S PCBs with the PLDs again!  Stock will be adjusted tonight to account for the additional availability.  Also, at least temporarily, we will be offering some of the ELM Programmer PCBs on the store.  However, we will likely be offering a variant of our own design (simplification of parts) in the near future.  Those PCBs will be added to the store as soon as I get a chance to add them.

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