Apple Attachment Unit Interface

Apple Attachment Unit Interface (AAUI) is a 14-position, 0.050-inch-spaced ribbon contact connector. Early Power Macintosh and Quadras[?] had an AAUI (Apple Attachment Unit Interface) port (rectangular shaped) for Ethernet, which requires a transceiver. To use twisted pair cabling[?], you would need to get a twisted pair transceiver for the computer with an AAUI port. Some Power Macintosh computers had both an AAUI and RJ-45 port; you can use one or the other, but not both.

The pin-out is:

  Pin   Signal Name     Signal Description
  ----  --------------  ---------------------------------
  1     FN Pwr          Power (+12V @ 2.1W or +5V @ 1.9W)
  2     DI-A            Data In circuit A
  3     DI-B            Data In circuit B
  4     VCC             Voltage Common
  5     CI-A            Control In circuit A
  6     CI-B            Control In circuit B
  7     +5V             +5 volts (from host)
  8     +5V             Secondary +5 volts (from host)
  9     DO-A            Data Out circuit A
  10    DO-B            Data Out circuit B
  11    VCC             Secondary Voltage Common
  12    NC              Reserved
  13    NC              Reserved
  14    FN Pwr          Secondary +12V @ 2.1W or +5V @ 1.9W
  Shell Protective Gnd  Protective Ground

AAUI signals have the same description, function, and electrical requirements as the AUI signals of the same name, as detailed in IEEE 802.3-1990 CSMA/CD Standard, section 7.