protech POS-3520, User Manual

Page: 19 / 109

Chapter 2 System Configuration
Page: 2-6
POS-3520 USER
’
S MANUAL
2-4. COM PORT & VGA CONNECTOR
There are four COM ports enhanced in this board namely: COM1,
COM2, COM3 and COM4.
Caution: When using a 72W power adaptor, do not set the voltage at
“12V” for three COM ports or above; otherwise, the system
may shut down due to power deficiency.
COM1: COM1 Connector
The COM1 Connector assignments are as follows:
PIN ASSIGNMENT
1 DCD2
2 RXD2
3 TXD2
4 DTR2
5 GND
6 DSR2
7 RTS2
8 CTS2
9 RI / +5V / +12V selectable
COM3: COM3 Connector
The pin assignments are as follows:
PIN ASSIGNMENT
1 DCD3
2 RXD3
3 TXD3
4 DTR3
5 GND
6 DSR3
7 RTS3
8 CTS3
9 RI / +5V / +12V selectable
10 NC
COM3
COM1