Set RS485 to 2-wire mode on cFP-2220

Here's an answer to a question that others might find useful: The RS485 on the PACs (cFP-2220 e.g.) is 4-wire, however it is possible to use it in 2-wire mode. That information is available in the manual and here on this site, however some of the details you need to know to get it working are not (the manual does not even say that you need to put a jumper between Rx+ and Tx+ and Rx- and Tx-): The detail I had to dig the most to find was the fact that you have to set a VISA serial property named wire mode...If you use the serial init VI or have your own that's a good place to expand the VISA resource property node used to set up the port and select serial-> wire mode. Set the mode to 2-wire auto and you are up and running.  According to the manual you will have to take into account that you will see the echo of the data you transmit, however with the wire mode set correctly that does not happen. Just like all other 2-wire equipment there is always the risk of replies not coming through because the switch to receive mode is slower than the response time, however for me that has not yet been a problem.  Message Edited by Mads on 08-14-2008 09:38 AM