I just ran into an issue where a VFD with option modules would kick back "Illegal Data Address" when attempting to read/write Holding Registers. Upon discussion with the manufacturer it was found that the unit ID for the various option modules is different than the VFD itself (255). I changed the Unit ID constant in the "Create TCP Session" vi and it fixed the issue, as well as using a property node to change the Unit ID after creating the TCP Session. Would you consider changing the constant to a control with the default being 255? Keep up the great work, I use this library daily and it has been a life saver. Thanks!
Hopefully a real quick question: I just started using this library, I got referred over here from the NI forums as this Modbus Library solved an issue that another MB library I was using had. That being said, I have not really taken a dive under the hood to figured out my problem. I was curious if anyone knew a quick fix before I started looking into it. When I try to build an application through the application builder that is using this MB library I get an error telling me that it can't build a broken VI without attaching the block diagram (which does fix the issue). It pointed me towards the "Read Session Valid.vi" as the issue. When I looked at that vi I can see a broken arrow with the error pointing towards the "unbundle by name". Can anyone verify that this block diagram is correct? I double checked I had the newest version of the library and still get this issue. Thanks!