ITX-D255R Mini-ITX Mother Board Manual
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2.7 I/O Connectors
2.7.1 COM#1 Port
Connector SPEC
Shape
Signal Description
Remark
DSUB 9Pin
Refer to below
No
Signal Description
No
Signal Description
RS-232
RS-422
RS-485
RS-232
RS-422
RS-485
1 DCD
-
- 6
DSR
-
-
2
RXD
RX (-)
-
7
RTS
TX (-)
Data (-)
3
TXD
TX (+)
Data (+)
8
CTS
RX (+)
-
4 DTR
-
- 9
RI
-
-
5
GND
GND
- - -
-
-
NOTE] COM#1 port support 3-types interface (RS-232 / RS-422 / RS-485). The Interface is changed by BIOS.
2.7.2 COM#2 / COM#3 Port
Connector SPEC
Shape
Signal Description
Remark
DSUB 9Pin
Refer to below
No
Signal Description
No
Signal Description
1 DCD
6
DSR
2 RXD
7
RTS
3 TXD
8
CTS
4
DTR
9
COM Power 5V or 12V
5 GND
10
-
NOTE] COM Power Voltage is selected by BIOS.
2.7.3 LAN Port
Connector SPEC
Shape
Signal Description
Remark
RJ-45 with LED
Refer to below
No
Signal Description
No
Signal Description
1
MD0 (+)
5
MD2 (+)
2
MD0 (-)
6
MD2 (-)
3
MD1 (+)
7
MD3 (+)
4
MD1 (-)
8
MD3 (-)