Serial Port Interface - AXIOMTEK sbc84500 User Manual

3.14 Serial Port Interface

The SBC84500VEA has four onboard serial ports, with
COM1,COM3,COM4 as RS-232 and COM2 as RS-232/422/485, both
selected via jumper setting. Both ports have +5V/12V power on pins 1 (+5V)
and 8 or pin 9 (+12V), depending on jumper selection. The RS-232's pin
assignments are listed below;
CON1 COM2 COM3 COM4
1 1 1 1
6 2 2 2
2 3 3 3
7 4 4 4
3 5 5 5
8 6 6 6
4 7 7 7
9 8 8 8
5 9 9 9
X 10 10 10
NOTE:
The COM2~COM4 ports of SBC84500VEA are pin header
type connectors and COM1 is a DB-9 connector.
The RS-422/485 pin assignment for COM2 is listed as follows;
Pin RS-422
1
TXD-
2
x
3
TXD+
4
x
5
RXD+
6
x
7 RXD-
8
x
9
GND
10 x
Hardware Description
SBC84500 User's Manual
Description
Data Carrier Detect (DCD)
Data Set Ready (DSR)
Receive Data (RXD)
Request to Send (RTS)
Transmit Data (TXD)
Clear to Send (CTS)
Data Terminal Ready (DTR)
Ring Indicator (RI)
Ground (GND)
GND
RS-485
DATA-
X
DATA+
X
X
X
X
X
GND
X
1 2
3 4
5
6
7
8
9
1 0
1 2
9 10
23