Chapter3 BIOS Configuration
PISA-E1 User’s Manual
27
COM3 Serial Port
COM3, a 10-pin header connector, is the onboard COM3 serial port of the
PISA-E1. The following table shows its pin assignments while it is configured as
RS-232 interface.
1
9
Pin #
Signal Name
1
DCD, Data carrier detect
2
RXD, Receive data
3
TXD, Transmit data
4
DTR, Data terminal ready
5
GND,
ground
6
DSR, Data set ready
7
RTS, Request to send
8
CTS, Clear to send
9
RI, Ring indicator
10
N.C.
COM4 Serial Port
COM4, a 10-pin header connector, is the onboard COM4 serial port of the
PISA-E1. The following table shows its pin assignments while it is configured as
RS-232, RS-422 or RS-485 interface.
1
9
Pin #
RS232 Mode
Signal Name
RS422/RS485 Mode
Signal Name
1
DCD, Data carrier detect
TX- (422/485)
2
RXD, Receive data
TX+ (422/485)
3
TXD, Transmit data
RX+ (422)
4
DTR, Data terminal ready
RX- (422)
5
GND,
ground
GND
6
DSR, Data set ready
N.C.
7
RTS, Request to send
N.C.
8
CTS, Clear to send
N.C.
9
RI, Ring indicator
N.C.
10
N.C. N.C.
