Serial Port 2 - Kontron PCI-946-1 Technical Reference Manual

2.5.2. Serial Port 2

The Serial Port 2 is available through the J8 10-pin connector, and supports both RS-232,
RS-422 and RS-485 operation modes.
Related Jumpers
BIOS Settings
The usual way to use the serial port is to issue signals through a 10-pin header/9-pin D-Sub
adapter cable (see description provided for the Serial Port 1).
2.5.2.1. RS-232 Mode
2.5.2.2. RS-422/RS-485 Modes
Downloaded from StockCheck.com
W2 and W3: to connect/disconnect Serial Port 2 termination resistors
Setups are described in Section 3.2 – Setting Jumpers
To setup the Serial Port 2, refer to Section 4.1.10: AWARD CMOS Setup Utility,
Integrated Peripherals Setup option
By default, the Serial Port 2 is configured for RS-232 operation mode. To change the
operating mode, refer to Section 4.1.10:
Peripherals Setup option .
Use the
AWARD CMOS Setup Utility
operation mode within RS-232, RS-422 or RS-485.
In RS-422 and RS-485 modes, transmitting and receiving use differential signals in
either full-duplex (RS-422) or party line (RS-485) communication.
Communicating with differential signals requires one pair of wires for RS-485 and two
pairs for RS-422 (one for transmission and one for reception).
For a better noise rejection, the use of twisted pair cable is highly recommended. This
will enable faster serial transmissions over greater distances than with the common RS-
232 cables.
If the board is installed at one end of the network and the Serial Port 2 is configured for
communicating in RS-422 or RS-485 mode, use the W2 and W3 jumpers to connect the
RS-485/RS-422 termination resistors (120 ohms) while the board is terminating the
network.
AWARD CMOS Setup Utility
, Integrated Peripherals
Setup option
2-9
Onboard Features
, Integrated
, to select the