13
1.4 COM
This interface can support RS-232 up to 4 ports and RS-422/485 up to 2 ports share
with RS-232. The transmitters/receivers of RS-232/422/485, which integrate ESD
protection, can reduce external ESD components. All the port functions can be
configured by BIOS setting before users make use of this interface.
1.4.1 Signal Descriptions
SMD
Pin
Name
Pin Type
Power Rail
Description
45
COM1 422TX-
/485D-/DCD#
Refer to
RS232/RS422/RS485
Standard
Refer to
RS232/RS422/RS485
Standard
422TX-/485D-/DCD#
47
COM1 422TX+
/485D+/RXD
422TX+/485D+/RXD
49
COM1 422RX+
/TXD
422RX+/TXD
51
COM1 422RX-
/DTR#
422RX-/DTR#
53 GND
GND
GND
GND
55
COM2 422TX-
/485D-/DCD#
Refer to
RS232/RS422/RS485
Standard
Refer to
RS232/RS422/RS485
Standard
422TX-/485D-/DCD#
57
COM2 422TX+
/485D+/RXD
422TX+/485D+/RXD
59
COM2 422RX+
/TXD
422RX+/TXD
61
COM2 422RX-
/DTR#
422RX-/DTR#
63 GND
GND
GND
GND
46 COM1 DSR#
Refer to
RS232/RS422/RS485
Standard
Refer to
RS232/RS422/RS485
Standard
DSR#
48 COM1 RTS#
RTS#
50 COM1 CTS#
CTS#
52 COM1 RI#
RI#
54 GND
GND
GND
GND
56 COM2 DSR#
Refer to
RS232/RS422/RS485
Standard
Refer to
RS232/RS422/RS485
Standard
DSR#
58 COM2 RTS#
RTS#
60 COM2 CTS#
CTS#