cbmeeks wrote:
I've seen a GAL20V8B used in a Commodore 64 PLA project recently. The GAL20V8B is obsolete but still easy to get from Aliexpress and the Minipro programmer supports it.
I assume the biggest pitfalls on using it would be:
1) Being obsolete, not a good idea for high volume products (not an issue for me). Only for small one-off projects.
2) Coming from China, expect a high failure rate and/or fakes. However, they are so dirt cheap that may not matter.
I'm thinking of buying a few just for giggles but seems like they would be a nice fit for some small glue logic here and there (especially prototyping).
What are you thoughts on that one or other GAL's?
Thanks
I used 1 x 22V10 in Ruby6502 and 2 in Ruby816.
Description of the 6502 board:
https://projects.drogon.net/6502-ruby/Picture of the '816 board:
Attachment:
ruby816-2.jpg [ 472.09 KiB | Viewed 2352 times ]
I buy Lattice parts from China - they're all board pulls that have (probably) been programmed just once (from what I can tell anyway). I've not had any issues - they're all worked for me, but it's possible I got lucky. I use a Genius G540 programmer off a WinXP Laptop, but I use something called GALasm running under Linux to generate the JED files.
I did buy a Minipro programmer, but (a) an early one and (b) turned out to be a "clone" and it won't program them. I'm told the next (current) version will program them and the still in-production Atmel (Microchip) ATL22V10 versions - I bought some of them new, but neither my old programmer nor the G540 will program them. (Currently I'm loath to buy another programmer, but I may in future)
If you can program them, then unless you want to be totally authentic to some historical design then spend the money and run! There is a fine-line between the purist retro and something a little newer though, but we had one time (mask) programmable logic chips in the late 70's/early 80's (ULAs) and user-programmable PALs in the early 80's too, so for me, it's retro enough, and is saving me 3-4 TTL chips and they enabled me to get my boards running code more or less immediately.
-Gordon
(edit to add photo+link)
_________________
--
Gordon Henderson.
See my
Ruby 6502 and 65816 SBC projects here:
https://projects.drogon.net/ruby/