Burt,
Thanks for the information. I find it interesting that the example code supplied with 8.2.1 proposes to read floating point values with a single read of a modbus variable. That is very misleading. Given the severe limits this puts on Modbus, I'm surprised that there is so little info available. This is more like a bug than a case of limited support.
I will be using the Lookout OPC server for my project. This may cost extra for a runtime license but I have no choice. I have too many point to read/write to mess with manipulation of 16 bit registers. I don't want to loose the flexibility of having shared variables connected directly to I/O points.
Len
