Posted 23 Sep 2005 Hi guys, please help. I am trying to communicate with Wipotec loadcell via RS232 port on CPM2A. The loadcell interface parameters as follows: 19200 bps, 8 data bits, odd parity, 1 stop bit, frame protocol transmission format: start code, STX data end code, ETX block control code, BCC what settings should I perform at CPM2A? i've tried various settings but has no respond from load cell just yet. Share this post Link to post Share on other sites
Posted 23 Sep 2005 Refer topics: serial connect RS232 communication For further information, search around this forum. Share this post Link to post Share on other sites
Posted 23 Sep 2005 first you have to set the DM for the RS232 on DM6645 to DM6649 so you can communicate with the loadcell , then you should read the chapter " Host link Commands " on the programming manual so you can configure the data tranfer Share this post Link to post Share on other sites
Posted 23 Sep 2005 A few questions to start with: Which port are you connecting to on the CPM2A? What software are you using? What cable are you using? You will need to set the comm port on the CPM2A to RS232 or No Protocol mode, and set the appropriate parameters (baud, start bits, stop bits and parity). You should also set the start and end characters. You can do this through the software or as stated above by directly entering the correct values in DM for the correct port. Cabling is often an issue. The Omron 9 pin port has a different pin out than an IBM 9 pin serial port. A "standard" null modem cable will NOT work. Hope this helps Share this post Link to post Share on other sites
Posted 23 Sep 2005 TXD-RXD Quickstart Programs @ MrPLC.com Share this post Link to post Share on other sites
Posted 23 Sep 2005 nice samples file Jay , thats a very usefull one for any beginner , communication setting is not always the easy part for the novice Share this post Link to post Share on other sites
Posted 24 Sep 2005 Hi guys, thanks for the advice but still fail to communicate. I'm using RS232C port on CPM2A, software CX-Programmer ver 4.0 I'm making the comm cable as follow; Load cell ----> CPM2A Sheild ------------- (1) FG Ground ------------(9) SG Transmit -----------(3) RD Receive ------------(2) SD My settings: no-protocol, 19200 bps, 1,8,1 odd, start code = STX, end code = 10 bytes After I have set these, do I need to send STX, data, ETX, BCC or eliminate STX? If i set my end code = ETX will it works? the loadcell is waiting for BCC after ETX. To test my communication, i only execute RXD instruction, will it works? Share this post Link to post Share on other sites
Posted 24 Sep 2005 Eliminate STX. If you set the end code for 10 bytes, then you must receive 10 bytes for the RXD to finish. Be sure to set correct number of bytes minus STX. Share this post Link to post Share on other sites