Loading ...
Sorry, an error occurred while loading the content.

Re: RCA COSMAC Microkit

Expand Messages
  • DougCrawford
    Jonathan: That was a very keen observation. It ll be cool if you are right! I guess that would mean that data transferring to peripheral cards for the outside
    Message 1 of 16 , Apr 18, 2013
    • 0 Attachment
      Jonathan: That was a very keen observation.
      It'll be cool if you are right!
      I guess that would mean that data transferring to peripheral
      cards for the outside world would have to re-invert before
      shipping the data out... or that would be a mess!

      --- In midatlanticretro@yahoogroups.com, Systems Glitch <systems.glitch@...> wrote:
      >
      > > Inverted BUS? I have not yet started trying to determine the purpose of the code.
      >
      > Some early bus structures were "inverted" in that a logic 0 was represented by what you would normally consider a logic 1 voltage. For TTL, this means that +3 and up is logic 0. The Ohio Scientific uses such a bus for their OSI-48 structure. Tranceivers usually exist with an inverted complement, like the 8T26/8T28.
      >
      > Thanks,
      > Jonathan
      >
    Your message has been successfully submitted and would be delivered to recipients shortly.