AXIOMTEK PICO840, User Manual

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PICO840/842 Pico-ITX Board
AX93283 I/O Board 27
CN3
CN4
3.5.3 COM1 Connector (CN3)
CN3 is the lower connector of the double-deck DB-9 connector. Only COM1 comes with
power capability on DCD and RI pins by setting jumpers (see section 3.4.1). The pin
assignments of RS-232/422/485 are listed in table below. If you need COM1 port to
support RS-422 or RS-485, please refer to section 5.4.
3.5.4 COM2 Connector (CN4)
CN4 is the upper connector of the double-deck DB-9 connector. The pin assignments of
RS-232/422/485 are listed in table below. If you need COM2 port to support RS-422 or
RS-485, please refer to section 5.4.
3.5.5 System Power Switch (CN5)
This switch is for turning on/off the system power.
Pin RS-232 RS-422 RS-485
10 DCD TX- Data-
11 RXD TX+ Data+
12 TXD RX+ N.C
13 DTR RX- N.C.
14 GND No use No use
15 DSR No use No use
16 RTS No use No use
17 CTS No use No use
18 RI No use No use
Pin RS-232 RS-422 RS-485
1 DCD TX- Data-
2 RXD TX+ Data+
3 TXD RX+ N.C
4 DTR RX- N.C.
5 GND No use No use
6 DSR No use No use
7 RTS No use No use
8 CTS No use No use
9 RI No use No use
Function Description
On Turn on/off system
Off Keep system status