CN20A: Serial Port DB-9 Male Connector (COM1)
PIN
Description
1
DATA CARRIER DETECT (DCD)
2
RECEIVE DATA (RXD)
3
TRANSMIT DATA (TXD)
4
DATA TERMINAL READY (DTR)
5
GROUND (GND)
6
DATA SET READY (DSR)
7
REQUEST TO SEND (RTS)
8
CLEAR TO SEND (CTS)
9
RING INDICATOR (RI)
COM2: Serial Port 2 x 5 Pin Header Connector
COM2 Support three modes: RS-232, RS-422, and RS-485 (For 2 x 5 pin header
connector)
RS-232 Mode
PIN
Description
1
DCD
3
RXD
5
TXD
7
DTR
9
GND
RS-422 Mode
PIN
Description
1
TXD-
3
TXD+
5
NC
7
NC
9
NC
PC 5150 Flat Panel PC
PIN
Description
2
DSR
4
RTS
6
CTX
8
RI
10
NC
PIN
Description
2
RX-
4
RX+
6
NC
8
Voltage
10
NC
129