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A Modbus TCP slave listens for connections from a master (client) and sends out a response or sets some system related parameter in accordance with the given query. Not only read data but we can also set data.
In order to read data from A Modbus TCP slave, you can use either Register Address or Register Number depending on which application you're utilizing.
For example, ComTestPro app uses Register Address:
To require the value of the current active SIM card slot, the Register Address would be 87, Number of Register would be 16 and the Command would be Read Holding Register(s).
After convert the value '7369 6D31' from HEX to ASCII, we will get the value 'sim1'.
Here's the link for the converter .
In order to set some device parameters in RUT955, the Registers Addresses available are 7/71//201/202/203/204/205/206/207/325.
From the side of ComTestPro app, it's necessary to change the Command from Read Holding Register(s) to Write Single Holding Register.
Please check the link below for more details.
More information can be found here:
You can download ComTestPro app from this link.
Should you need any additional information please let us know.