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Programmable Array Logic

Programmable Array Logic (PAL) is a family of programmable logic device semiconductors used to implement logic functions in digital circuits that was introduced by Monolithic Memories, Inc. (MMI) in March 1978. MMI obtained a registered trademark on the term PAL for use in "Programmable Semiconductor Logic Circuits". The trademark is currently held by Lattice Semiconductor. PAL devices consisted of a small PROM (programmable read-only memory) core and additional output logic used to implement particular desired logic functions with few components. Using specialized machines, PAL devices were "field-programmable". PALs were available in several variants: * "One-time programmable" (OTP) devices could not be updated and reused after initial programming. (MMI also offered a similar family called HAL, or "hard array logic", which were like PAL devices except that they were mask-programmed at the factory.) * UV erasable versions (e.g.: PALCxxxxx e.g.: PALC22V10) had a quartz window over the chip die and could be erased for re-use with an ultraviolet light source just like an EPROM. * Later versions (PALCExxx e.g.: PALCE22V10) were flash erasable devices. In most applications, electrically erasable GALs are now deployed as pin-compatible direct replacements for one-time programmable PALs.

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Article summary

Programmable Array Logic (PAL) is a family of programmable logic device semiconductors used to implement logic functions in digital circuits that was introduced by Monolithic Memories, Inc. (MMI) in March 1978. MMI obtained a registered trademark on the term PAL for use in "Programmable Semiconductor Logic Circuits". The trademark is currently held by Lattice Semiconductor. PAL devices consisted of a small PROM (programmable read-only memory) core and additional output logic used to implement particular desired logic functions with few components. Using specialized machines, PAL devices were "field-programmable". PALs were available in several variants: * "One-time programmable" (OTP) devices could not be updated and reused after initial programming. (MMI also offered a similar family called HAL, or "hard array logic", which were like PAL devices except that they were mask-programmed at the factory.) * UV erasable versions (e.g.: PALCxxxxx e.g.: PALC22V10) had a quartz window over the chip die and could be erased for re-use with an ultraviolet light source just like an EPROM. * Later versions (PALCExxx e.g.: PALCE22V10) were flash erasable devices. In most applications, electrically erasable GALs are now deployed as pin-compatible direct replacements for one-time programmable PALs.

Key claims

  1. release date: 1983 — source: Wikipedia · confidence 0.95
  2. release date: 1984 — source: Wikipedia · confidence 0.95

Discussion questions

  1. Summarise the article in your own words. Which single claim would you verify first, and why?
  2. The record states that the release date is "1983". What evidence would count against this claim?
  3. The record states that the release date is "1984". What evidence would count against this claim?
  4. Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
  5. If two sources disagreed about one of these facts, what would you need in order to trust one over the other?

Bibliography

  1. Wikipedia https://en.wikipedia.org/w/index.php?oldid=1373769163

Key claims and bibliography are generated from the same tracked claims and sources as the article page.