User`s manual

Universal PCI Board User’s Manual Hardware Installation
2-10
CP-134U V2
Onboard termination resistors can be activated individually for each serial port using jumpers JP1
through JP4. JP1 corresponds to serial port 1. Short the jumper pins to activate the termination
resistor; leave the jumper pins open to bypass the termination resistor.
The onboard DIP switches, S1 and S2, are used to select RS-422 or RS-485 mode for each serial port.
Switches 1 through 4 on each bank correspond to the 4 serial ports. S2 selects between RS-422 and
RS-485; S1 selects between 2-wire and 4-wire RS-485. In addition, ports 1 and 2 can be set
individually to RS-232 mode using the on-board 30-pin jumpers, as follows:
RS422
RS232RS485
Port1
Port2
RS422
RS232RS485
Port1
Port2
RS-422 or RS-485 mode:
Use the jumper to cover the left
two columns of jumper pins.
RS-232 mode:
Use the jumper to cover the right
two columns of jumper pins.