Instruction manual

Appendix A Genesis MP68 ◆
The Serial Ports
The Genesis MP Systems have two serial ports located on the
back panel. Both of these ports use 9-pin circular mini-DIN sock-
ets. The serial port sockets will accept either 8 or 9-pin plugs.
With external modules connected to these serial ports, the
Genesis MP System can communicate with a variety of ISDN and
other telephony transmission products. The serial port sockets can
be independently programmed for asynchronous or synchronous
communication formats up to baud rates of 9600 (this includes
AppleTalk and Apple GeoPort protocols).
Serial Port Connector - Pin Assignments
Pin Name Function
1 HSKo Handshake output
2 HSKi Handshake input or external clock
3 TxD- Transmit Data-
4 Gnd Ground
5 RxD- Receive data-
6 TxD+ Transmit data+
7* GPi General-purpose input
8 RxD+ Receive Data
9** +5V Power to external device(s) (100mA max)
* Pin 7 includes the GPi (general-purpose input signal).
* Pin 9 on provides +5 power from the ADB power supply. An
external device should not exceed 1000 mA from this pin.
The total current available for all devices connected to the +5V
supply for the ADB and the serial ports is 500 mA.
CAUTION
Excessive current will cause a circuit breaker to interrupt the +5V
supply. The breaker will automatically reset when the load returns
to normal.
∆
!