Getting started with GALs

"GALS," not as in what creepy old guys call women, but GALs as in "Generic Logic Arrays."
GALs are the simplest member of the programmable logic family that also includes CPLDs and FPGAs. They are the modern replacement for the one-time programmable PAL devices that were first introduced in the late 1970's. Unlike PALs, GALs can be erased and reprogrammed many times. And unlike CPLDs and FPGAs, GALs don't require using a hardware synthesis language like VHDL or Verilog, or any other special design tools. Although it's possible to use fancier tools to configure GALs, the simplest method is just to write logic equations in a plain text file, defining each output in terms of the inputs. Run your equations through a command-line tool to create the binary GAL data, and you're ready to go. Easy as pie!
Posted by Gareth Branwyn |
Apr 3, 2008 04:00 PM
Computers, Electronics |
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Comments
Oldest comments listed first.
| Posted by: on April 3, 2008 at 11:31 PM |
But Verilog IS just like writing logic equations to a plain text file. It's really a simple thing to learn.
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Posted by: Pelrun on April 4, 2008 at 6:07 AM |
Ten minutes after I read this post I bid on a batch of *sixty* GAL's on Ebay (seems like there isn't a decent Oz-local supply in small quantities, sigh.)
Guess I'm not going to need any discreet parts for a long time to come... :D
Well, except for those in the programmer, obviously.
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Posted by: Pelrun on April 5, 2008 at 7:12 PM |
I guess that'll teach me to comment about an ebay auction I'm in before it finishes...
To the guy who sniped me on the auction, quail as I impotently shake my fist at you! *shake*
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