Modbus TCP overSerial TRB145


I have problem with Modbus TCP overSerial TRB145 firmware version higher than

I can read max. 9 register

When i try to read 10 i have informations:

Request failed, result: Failed to get response: Operation timed out

When i back to firmware TRB1_R_00.07.06.10. everthing is fine.

Is the problem known?

Best regards



Could you please confirm if this issue persists with TRB1_R_00.07.07.3 firmware version? You can download firmware here: TRB145 Firmware Downloads - Teltonika Networks Wiki

Best Regards,


Problem is the same like in version 07.07.02 but I checked more queries and it turned out that the problem only occurs when asking about 10 or 13 registers ( Register count / Values ). :wink:

Best Regards


Thank you for confirming that. I have reported this issue to our development department, and once I receive any updates, I will get back to you.

Best Regards,

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Could you please specify or provide a topology of how you have tested it?

Our developers were not able to reproduce the issue. Here is their test topology and configuration:

Best Regards,

Good day,

I am having the same problem on TRB145 and TRB142. It worked correctly on 7.6.10, but not 7.7.3. I have recreated the problem using a similar configuration to your diagram above.

In my case, I can’t read holding register 4, 11, 14. I am only reading 1 holding register at a time, as “16bitINT, high byte first”. The error says “Request failed, result: Failed to get response: Operation timed out”.

The serial gateway is configured at 9600/8/1/none/none. Disabling CRC verification doesn’t make a difference.

I am currently testing on a remote TRB145. But I had a similar problem a few weeks ago on a TRB142. I downgraded the TRB142 to 7.6 and the problem disappeared. I think that the registers that I had a problem with might have been different on the TRB142.