Rs-422/485 Settings And Information - Brainboxes PX-101 Product Manual

Connect the Port 2 DTR line, pin 4 to the other PC DCD, pin 8 and CTS, pin 5, lines. Also, connect up the
other PC DTR line, pin 20 to the Port 2 DCD, pin 1 and CTS, pin 8, lines.
This allows the receiving device to signal when it can no longer accept data. The receiving device sets DTR
false when it is unable to receive any more data. The sending device reads DTR on its CTS and DCD pins. It
should stop sending when CTS goes false.
Connect the Port 2 RTS line, pin 7, to the other PC DSR line, pin 6. Also, connect the other PC RTS line, pin
4, to the Port 2 DSR line, pin 6. This RTS line is used to let the other device know that it is ready for data
exchange.

2.9. RS-422/485 Settings and Information

To achieve RS-485 Half Duplex Communications, it is necessary to short Pins 1 and 6 together, and
•
pins 2 and 7 must also be physically shorted together. This can be done via the on-board Multi-plex
jumpers.
Once your wiring is setup, you will also need to set the card to FULL or HALF Duplex mode in the
•
software.
PX Range Product Manual
This diagram shows the PX-310 where
Port 2 is set up for half-duplex by
placing jumpers across HDX2+ and
HDX2-
In the example shown, Port 1 is set up
for full duplex as there are no jumpers
across HDX1+ or HDX1-
Version 2.3 © Copyright Brainboxes Limited 2013 Page 24 of 45