I have a question around Modbus communications, specifically the poll duration. While working on items in our test environment we enable a Modbus data source with the server’s home IP (127.0.0.1) and port of 502. The server has no Modbus device attached it to and no simulator or anything listening to port 502.
As expected, the Slave Monitor is 0 since there is no Modbus device for Mango to talk to.
What we get that is somewhat unexpected is successful polls. In the Runtime Status tab, the polls are succeeding, taking about 3.2 seconds each.
We thought we’d see timeouts instead of successful polls. Are there any ideas why the polls aren’t timing out? Is the server sending TCP/IP info back to Mango, and that is triggering the successful poll?
I did turn on I/O logging for the data source, but nothing gets logged outside of the data source being enabled and disabled.