The value assignment commands to Modbus Register are configured as follows:

1. Go to the Values tab (1) on the Modbus Rule object settings panel.
   
2. In the Value column (2), enter the channel value.
3. In the Command text column (3), enter the message which will be received when the register takes on the specified value.
4. Click the Apply button (4) to save the changes.

The value assignment commands to Modbus Register are now configured.