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Modbus server - reading holding registers above 7167

abousezimecabousezimec
edited May 2021 in PLCnext Engineer
Hello,

I'm trying to use the modbus server from library Modbus_TCP_9.
We try to replicate an existing device which uses address ranges for holding registers up to 9000+.

When, from the client, I try to read the registers, I get illegal data address.
In the doc of the library it states that the range for holding registers is 0-65535.
However everything above 7167 is not readable (illegal data address).

Is there a setting somewhere to be set in order to allow reading above 7167?

Thanks,

Kind regards,

Adrien

Comments

  • Martin [PLCnext Technology Team]Martin [PLCnext Technology Team]
    Hi Adrien,
    The developers have reproduced this and identified it as a bug in the current version of the Modbus library.
    It will be fixed it in the next version of this library (Modbus_TCP_10).
    ~ Martin.
  • adrien.bousezadrien.bousez

    Hello Martin,


    Do you know if the error has been fixed in the meanwhile?

    I can't find anything about it in the release notes.

    Thanks,


    Adrien

  • Martin [PLCnext Technology Team]Martin [PLCnext Technology Team]

    Sorry for the delay.

    Yes, this was fixed in version 10 of the Modbus TCP library, but unfortunately this was not mentioned in the release notes.

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