Group Description

The RCA CDP1802 COSMAC microprocessor was the basis for several hobbyist computers in the mid 70s and early 80s. Join this group to discuss these old computers or share your 1802 experiences. 

Visit for more on the history of 1802 microcomputing, data sheets, articles, photos, and more --- including a complete archive of Ipso Facto newsletters.

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Top Hashtags [See All]

  • #Serial Serial communications 6 threads
  • #SuperElf Quest Electronics SuperElf 4 threads
  • #Homebrew Original 1802 computer creations 4 threads
  • #ThisGroup Messages about the group itself 4 threads
  • #Assembler 1802 assemblers and cross-assemblers 4 threads
  • #Arduino Arduino related projects 3 threads
  • #Forth Forth language 3 threads
  • #MembershipCard 1802 membership card computer by Lee Hart 2 threads
  • #Microtutor RCA Microtutor 2 threads

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