Programmable Array Logic

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Programmable Array Logic (usually referred to by the acronym, PAL) is the name for a variety of chips which contain a class of configurable blocks of logic elements; the programming is done with fusible links.

They contain programmable arrays of AND gates, whose outputs are led into fixed OR gates. Different models offered different-sized arrays. High-end PALs offered registered outputs, which could be fed back into the PAL, allowing them to make use of prior state. Some PALs allowed the output of several of the OR gates to be fed into an XOR gate which fed the latch at the output.

See also

Further reading

  • PAL Programmable Array Logic Handbook, Monolithic Memories, Inc., Santa Clara