Monitor I/O server communications status
- Last UpdatedApr 07, 2025
- 2 minute read
For each topic name being used, you can use a built-in discrete item, Status, to monitor communication status with the I/O Server program. The Status item is set to 0 when a communication failure occurs. The Status item is set to 1 when communicating normally with the I/O Server program.
Note: When you monitor the status of a topic using the IOStatus item, at least one I/O point must be active for the monitored topic.
From the InTouch HMI, you can read the state of the server communications by defining a tag and associating it with the topic configured for the device by using the word Status as the Item Name. For example, if WindowViewer is communicating with a PLC using the Modbus DAServer, the Access Name definition is similar to the following example:

To monitor the status of all communication to the topic PLC1, create the following tag definition:

In Excel, you can read the status of the PLC communications by entering the following formula in a cell:
=SIMULATE|PLC1!'STATUS'