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we have a problem using this table:

We would like to send the data from this IO:

Digital galvanically isolated input (DIN2) state 137 138 2 32 bit integer

We set the setting like this on RUT955 - the communication is working, but instead of sending two registers (137 and 138) we actually send "2". We set it to 2 as it says at the top of the column that you must type there "Register count", but it seems it only sends the value you type in. 

Is there some kind of specific syntax you have to use in this 2 columns to make it work like we would want to?

As said, First register we set to 137 (for Digital galvanically isolated input (DIN2) state) and Register count for 2 registers (137 and 138 as shown in the table above). 

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Thanks for contacting TELTONIKA | Crowd-support forum.

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.

Best regards,



thank you for your answer. We managed to make it work.

One additional question - the analog input:

Analog input (PIN 9) value 141 142 2 32 bit unsigned integer

Is read and sent in V (0 - 24 V), is it possible somehow to read and send it as current loop (4-20mA)?

In the settings (services/io/general) you can select Analog Input (for V) and Analog Current Loop (for mA), but changing that value has no effect on the register, its always sent as V...