rtd cpuModule CMC6686GX, User Manual

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47
Multifunction Connector, P8
or CN5
The Multifunction connector on P8 or CN5 implements the following functions:
• Speaker output
• AT keyboard
• System reset input
• Watchdog Timer output
• Battery Input
The following table gives the pinout of the Multifunction connector.
Facing the connector pins, the pinout is:
Speaker
A speaker output is available on pins 1 and 2of the Multifunction connector. These outputs are con-
trolled by a transistor to supply 0.1 watt of power to an external speaker. The external speaker should
have 8 ohm impedance and be connected between pins 1 and 2.
Keyboard
An AT compatible keyboard can be connected to the Multifunction connector. Usually PC key-
boards come with a cable ending with a 5-pin male ’DIN’ connector. The following table lists the
relationship between the Multifunction connector pins and a standard ’DIN’ keyboard connector.
To ensure correct operation, check that the keyboard is either an AT compatible keyboard or a swit-
chable XT/AT keyboard set to AT mode. Switchable keyboards are usually set by a switch on the
back or bottom of the keyboard.
P8 or CN5
Pin Signal Function in/out
1 SPKR+ Speaker output (open collector) out
2 SPKR- Speaker output (+5 volts) out
3 RESET Manual push button reset in
4 -- Not connected --
5 KBD Keyboard Data in
6 KBC Keyboard Clock out
7 GND Ground --
8 KBP Keyboard Power (+5 volts) out
9 BAT Battery input in
10 -- Not Connected --
9 7 5 3 1
BAT GND KBD RESET SPKR+
KBP KBC SPKR-
10 8 6 4 2