Commands And Events

The Modbus module has the following Commands and Events:

Events

NameDescriptionEvent Type
ExternalItems

Timer event for handling of external items. By default, the command 'HandleExternalItems' is connected to this event, but that can be modified. The timer resolution is specified by the 'ExchangeRate' property.

Timer
ReadDone

An event signalled when a read of modbus slave has finished.

Normal
WriteDone

An event signalled when a write to modbus slave has finished.

Normal
PollDone

An event signalled when a complete poll operation of slave has finished.

User case: Connect this event to "Start Polling" command of another Modbus module accessing same slave without polling rate to avoid to modules to access same slave simultaneously, to reduce risk of corrupt response.

Normal

Commands

NameDescriptionCommand Type
HandleExternalItems

Command for reading external items. When fired, the module will read all its external items, and update/notify the ones that has changed.

Synchronous
Start Polling

Initiate a poll from slave.

Asynchronous
UpdateItemTimestamp

Command used for updating the value of the item specified in the 'TimeReferenceItem' property, when configured.

Synchronous

See also Commands And Events