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Fetch A : X = bus[A]Store V A : bus[A] = V

On TTY interrupt:
  if bus[TTY.status] == TTY.read ok
    TTY.in buffer[TTY.next in++] = bus[TTY.data]
  else if bus[TTY.status] == TTY.write ok
    if TTY.out buffer size > 0
      bus[TTY.data] = TTY.out buffer[TTY.next out++]
      TTY.out buffer size--      
  else // deal with other TTY status values
| This page last modified on 2012 January 28. |