11681023 Rev A
6
© 2011 UTC RETAIL.
All rights reserved.
COM Port Power
The RS232 ports (COM1, COM2) can be configured to supply power to pin 9 of their DB9
connector. COM2 is set by default to have +5VDC on its pin 9.
The pin 9 power options are 0, +5, or +12VDC.
Power selection jumpers are located on the motherboard. The table below summarizes the
RS232 DB9 pin definitions:
PIN NO.
1
2
3
4
5
6
7
8
9
Signal
CD
RX
TX
DTR
GND
DSR
RTS
CTS
RI or 5V/12V
output
J1: Select RI/VOLTAGE output for DB9 pin 9 of Port 1.
J2: Select RI/VOLTAGE output for DB9 pin 9 of Port 2.
Pins jumpered
Pin 9 Setting
1 – 2
RI
3 – 4
+5V
5 – 6
+12V
COM1 Power (pin 1)
COM2 Power (pin 1)
COM Ports
