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I tested TCP Modbus Slave with the firmware RUT9XX_R_00.06.05.1.   All was fine between the registers 1 to 184 (only I found some mistakes in some registers).    When  request the registers over 185 (i.e. the registers with the info of the SIMs) I received error from modbus that device not support this registers.

I Updated to the last firmware (RUT9XX_R_00.06.06.1), and now the THE TCP Modbus Slave is not working, after one query I received error, and I need to wait several seconds.    And now, there are a lot changes in the registers.   Only some variables maintain the same registers.

when you will fix the issues with the modbus Slave? 




We have also seen issues with modbus communication after update to latest firmware (RUT9XX_R_00.06.06.1). The issue here seems to be that the modbus slave closes the connection after each request. I don't know if this is a bug or expected behaviour. Our solution was to rewrite the modbus master code (we are using a nodejs backend) check if the connection is open and if not pen the connection on each request. I'm not able to post the code snippet here due to the ridiculous post limit of 12000 chars.

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I recommend double-checking if you are using correct Modbus registers when reading data from router:

Also, could you please provide more information how we could reproduce this issue on our side, and can you please PM me with the troubleshoot file (System -> Administration -> Troubleshoot) when issue persist?

Please, let me know.

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Hi torgilfolger,

Try this TEST firmware:

In Services -> Modbus -> Modbus TCP slave there should be option Keep persistent connection , check it and see if issue persist.

Attached TEST Firmware release is for this particular issue.
Please check if this specific function works properly now.
Since this is a TEST version of the Firmware, designed to address specific issues, use it only with a handful of devices; you should not use it for your whole fleet.
Once we receive positive feedback from you – these changes will be included into next Master Firmware release version.

Note: without final confirmation that the issue has been resolved these changes will not be included into Master Firmware version, hence shall not be included from the Factory.