External Device Connector Pin AssignmentsC-6 014–001867VTC Interface ConnectorThe VTC controller provides a standard IEEE 802.3 local area network interfacethrough a 15-pin sub-D connector. This connector accepts an Access Unit Interface(AUI) cable. The AUI cable connects the computer to an external Media AttachmentUnit (MAU). The MAU contains the Ethernet transceiver and the Media DependentInterface (MDI) for connection to the physical network. Figure C–3 shows thesignals and pin numbers for the VTC external connector.Pin Circuit Name1 CI–S (Control In circuit shield)2 CI–A (Control In circuit A)3 DO–A (Data Out circuit A)4 DI–S (Data In circuit shield)5 DI–A (Data In circuit A)6 VC (Voltage common)7 CO–A (Control Out circuit A)8 CO–S (Control Out circuit shield)9 CI–B (Control In circuit B)10 DO–B (Data Out circuit B)11 DO–S (Data Out circuit shield)12 DI–B (Data In circuit B)13 VP (Voltage plus)14 VS (Voltage shield)15 CO–B (Control Out circuit B)Pin 1Pin 8Pin 9Pin 15VTC connector to LAN(female)The connector shell acts as a protective groundFigure C–3 VTC Connector Signals
