I have a calibration program written in Labview and need to change the vi's written for communicating with our Modbus device (old ARCOM cards which are now made by ElecSys). I have used some example programs on ni.com. The "MB Serial Example Master.vi" sees each transducer on the Modbus device and seems to work correctly. However, the example vi "MB Serial Example slave.vi" never works and throws an unknown error. For now, I am not concerned with the error. What I would like to know is if there are better drivers for communicating with the Modbus device in which I can view all the transmitter data registers and modify them.
Currently we have a program written which pulls (through the ARCOM) the tag names and PV values from our transmitters (Rosemount 3051). This program works very well for doing this. But, my goal is to pull the transmitter address numbers and change all to zero, then pull the tag names, change all damping values to 0.4s, change all low/high side range values, and trim each device in an automated and sequential fashion. From my reading thus far, I will need to pull and modify the registers for each transmitter which seem to be stored on the modbus device. I really am not an expert with Modbus. But, once I get headed in the right direction, I will be able to figure out many details on my own.
