GAL/PAL Creation

[+dhe]

About a year ago I purchased a TI866+. I'd like to get the experience of creating a simple GAL - maybe just as simple as two pins forming a and gate with one output.

 

  I found this PDF online which looks pretty detailed.

       https://retrobrewcomputers.org/n8vem-pbwiki-archive/0/82152589/Programmable%20logic%20devices%20-%20v1.6.pdf

 

I'd like to see what GAL/PAL compilation software you recommend?

 

  Also, there is a picture of a test rig, does anyone know of a PCB that someone has created to do this kind of testing?

 

 

 

 

[Stuart]

The sites I bookmarked when starting to play with GALs were:

-- http://www.retrotechnology.com/herbs_stuff/gal.html

-- http://sss-mag.com/pdf/PLDTUTOR.pdf

-- https://web.archive.org/web/20201211195829/http://www.uchobby.com/index.php/2008/03/30/gals-for-electronics-hobby/

 

The last site has a link to the National Semiconductor Opal jr toolkit which is what I use ... but it is DOS-based so you need to run it in DOSbox on a Windows machine. You might be able to find something a bit more modern.

 

Never seen a PCB to do that type of testing. I experimented by programming a GAL as various TTL chips and made a little adaptor to map the GAL pins to an IC header I could plug in to replace the TTL chip for testing on one of my processor boards.

 

 

[atrax27407]

This might help you get started. BTW, I just ordered 10 Lattice 16V8 GALs from an eBay supplier that I frequently use. If you are looking for the old PALs, check the Hodge16 seller on eBay. He has good collections for a few $$.

Generic Array Logic Devices.pdf

[Shift838]

On 2/24/2022 at 2:59 PM, dhe said:

About a year ago I purchased a TI866+. I'd like to get the experience of creating a simple GAL - maybe just as simple as two pins forming a and gate with one output.

 

  I found this PDF online which looks pretty detailed.

       https://retrobrewcomputers.org/n8vem-pbwiki-archive/0/82152589/Programmable%20logic%20devices%20-%20v1.6.pdf

 

I'd like to see what GAL/PAL compilation software you recommend?

 

  Also, there is a picture of a test rig, does anyone know of a PCB that someone has created to do this kind of testing?

 

 

 

 

i wired up a test jig based on Fritz442 instructions.  i put it all in a priority mail box!  This one was setup for the RAVE99 PAL.

 

What you don't see inside my priority mail box is the arduino microcrontroller.

 

I coded a program that would whip through the RAVE99 PAL and decode it and log it to an output file as well as on the serial monitor.  Fritz442's schematic is great but when I saw how many combinations I had to do to manually flip each switch, i figured let some arduino code do it.

 

The Rave99 PAL proved to be a bit more complicated and took some messing around with on Fritz's part before we had a good code to work.  

 

I even