Apple GeoPort connector

#Computer#Serial Interfaces#Apple

The back panel of all Power Macintosh models contain two I/O ports for serial telecommunication data.

9 pin Apple mini din connector pin-out & layout

9 pin Apple mini din connector  at the end of the peripheral cable, from the front of the connector

Both sockets accept 9-pin plugs, allowing either port to be independently programmed for asynchronous or synchronous communication formats up to 9600 bps. This includes AppleTalk and the full range of Apple GeoPort protocols.

1SCLK (out) Reset pod or get pod attention 
2Sync (in)/SCLK (in) Serial clock from pod (up to 920 Kbit/sec.) 
3TxD- Transmit - 
4Gnd/shield Ground 
5RxD- Receive - 
6TxD+ Transmit + 
7Wake up/TxHS Wake up CPU or do DMA handshake 
8RxD+ Receive + 
9+5V Power to pod (350 mA maximum) 

Apple Duo Dock Modem Adapter Card connector

Apple IIc Joystick Connector