AR-B1474 User¡¦s Guide
3-2
3.2 SYSTEM SETTING
Jumper pins allow you to set specific system parameters. Set them by changing the pin location of jumper blocks.
(A jumper block is a small plastic-encased conductor that slips over the pins.) To change a jumper setting, remove
the jumper from its current location with your fingers or small needle-nosed pliers. Place the jumper over the two
pins designated for the desired setting. Press the jumper evenly onto the pins. Be careful not to bend the pins.
We will show the locations of the AR-B1474 jumper pins, and the factory-default setting.
CAUTION: Do not touch any electronic component unless you are safely grounded. Wear a grounded wrist strap
or touch an exposed metal part of the system unit chassis. The static discharges from your fingers can
permanently damage electronic components.
3.2.1 Serial Port
(1) RS-485 Adapter Select (JP3 & JP11)
JP3 and JP11 can be set independently. JP3 selects COM-A port and JP11 selects COM-B port.
1
2
3
JP3 -- COM-A
1
2
3
Reserved for Acrosser's
RS-485 adapter used only
RS-232C
(Factory Preset)
Figure 3-2 JP3: RS-485 Adapter Select for COM-A
1 2 3
JP11 -- COM-B
1 2 3
Reserved for Acrosser's
RS-485 adapter used only
RS-232C
(Factory Preset)
Figure 3-3 JP11: RS-485 Adapter Select—COM-B
(2) RS-232 Connector (DB1 & DB2)
There are two serial ports with EIA RS-232C interface on the AR-B1474. COM-A and COM-B use two on-board D-
type 9-pin male connectors (DB1 & DB2). If you want to configure the serial port, please refer to the BIOS
configuration.
DB1 (COM A)
6-DSR
7-RTS
8-CTS
9-RI
1-DCD
2 RXD
3 TXD
4-DTR
5 GND
DB2 (COM B)
6-DSR
7-RTS
8-CTS
9-RI
1-DCD
2 RXD
3 TXD
4-DTR
5 GND
Figure 3-4 DB1 & DB2: RS-232 Connector