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]

  • #Homebrew Original 1802 computer creations 31 topics
  • #Serial Serial communications 17 topics
  • #ELF Classic or minimal ELF builds 17 topics
  • #MembershipCard 1802 membership card computer by Lee Hart 16 topics
  • #Assembler 1802 assemblers and cross-assemblers 11 topics
  • #ThisGroup Messages about the group itself 9 topics
  • #microboards 9 topics
  • #VIP RCA's COSMAC VIP 8 topics
  • #ELF2K Spare Time Gizmos' ELF 2000 7 topics
  • #Emulator Emulation of 1802 based computers 7 topics

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