Technically, when it comes to Modbus "Customer Register Block", you can put any information in it, even read Modbus Serial Master database and write desired information to this block. However, we do not have any references or instructions how to do what you desire. That would require to write customer script on the router, to periodically read information, parse it and the write it to this new register block.
Instead of trying achieve such unique solution to re-read information from the router, maybe once of other existing options is suitable for you? Options, which are available at this moment in time are:
- To use "Modbus Serial Master" functionality in combination with "Data to Server" functionality, so that read Modbus information from your RS485 device would be sent to your servers via MQTT or HTTP(S) protocols.
- To acquire information via MQTT directly by using "Services -> Modbus -> MQTT Gateway" functionality.