Modbus address mapping

When using Modbus address mapping, does the Ignition server poll all entries that are set up, or does it only poll entries that are requested by tags etc.?

We have a system where a few hundred registers are scattered around a range of several thousand PLC registers. It would easier to set up a single big block of registers so that we can request the data using the PLC registers, but not if it's actually going to be trying to read thousands of registers.

Only those you subscribe to.

Regardless, for various reasons, I'd recommend not using the addressing mapping at all. It's a poorly thought out design that introduces unnecessary indirection and confusion, for no benefit.

1 Like

Pssst! My alternate driver offers OPC browsing directly on the standard address names....

/shameless plug

1 Like