Polling tags Individually

We are having an issue seeing tag state changes on a slave device. It has been suggested by the slave device owner that it is because we are polling multiple tags at once.
Is it possible to poll tags individually? How can this be achieved?


What driver? If a flavor of Modbus, turning off “span gaps” could help. And or reducing the maximum number of registers per request.

Also, just for my future (non-) purchasing file: what brand and model? Because that is a technically lame excuse.

We are polling Modbus RTU (set as digital coil inputs on their end) from a struxureware automation server through our Moxa gateway. We are setup to read these points as digital inputs in the tag config.
Span gaps is currently left unticked. We also have the following setup:

Max Holding Registers Per Request - 125
Max Input Registers Per Request - 125
Max Coils Per Request - 2000
Max Discrete Inputs Per Request - 2000

Any other info would be appreciated.

Is there really a serial port in the data path? Does such a serious product not support Modbus TCP?

Regardless, for starters, cut all of the Max per Request values in half. Smaller packets on a serial line == less chance any specific packet is broken by noise.

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