BI94GS-IAC
13
JCOM1A /JCOM1B : Serial port Connectors
The motherboard has Serial Port Connectors for connecting RS-232 Port. Only
JCOM1A supports RS-422/485.
RS-232
RS-
422
RS-
485
Pin
Assignment
1
Carrier detect (DCD)
TX-
TX-
2
Received data (RXD)
TX
TX
3
Transmitted data (TXD)
RX
NC
4
Data terminal ready (DTR)
RX-
NC
5
Signal ground (GND)
GND
GND
6
Data set ready (DSR)
NC
NC
7
Request to send (RTS)
NC
NC
8
Clear to send (CTS)
NC
NC
J C O M 1 A
J C O M 1 B
9 Ring
NC
NC
JSEL1/JSEL2: Ring/5V/12V Switch Header for JCOM1A/JCOM1B
JSEL1 and JSEL2 respectively control Pin 9 of JCOM1A/JCOM1B for
Ring/5V/12V.
1
2
5
6
Pin 1-2 Close:
Ring (Default)
1
2
5
6
Pin 3-4 Close:
5V
1
2
JSEL2 JSEL1
5
6
1
2
5
6
Pin 5-6 Close:
12V
