Computers & Mobile Technology
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!

GALS for Electronics Hobby


Gareth Branwyn is a freelance writer and the former Editorial Director of Maker Media. He is the author or editor of over a dozen books on technology, DIY, and geek culture. He is currently a contributor to Boing Boing, Wink Books, and Wink Fun. And he has a new best-of writing collection and “lazy man’s memoir,” called Borg Like Me.

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