Question

Hello,

Ive enabled the Modbus TCP Slave function in the RUT955. I've used both QModmaster and Pymodbus to poll the router. When I use QModmaster, I do not receive a response. When i use Pymodbus, i receive a response that does not correspond with the request. I've confirmed this with wireshark, which also acknowledges that the response of the router is malformed/not correct. On a different PC, i also used Modbus Poll, here the system seemed to work fine for several registers, but stopped working from around input register 143. Is this a known problem? Can we fix this?

Kind regards,

Mark Boere

Answer 1

Hello,

What is the firmware version that your device is running?

Do you have Keep persistent connection option enabled in MODBUS TCP slave configuration?

Since register 143 indicates GPS data, do you have GPS enabled on the router with a location fix?

Could you share the packet capture file with malformed packets by attaching it to your question?

Having tested RUT955 with QModmaster, I have not had issues with the following configuration:

Best regards,

Comments

Hi,

Please see my private message, i cannot send it here as it says i exceed the maximum length of 12000 characters even though it is much less.

Kind regards,

Mark