Modbus R3-4 released

[Mark Rivers via Tech-talk <tech-talk at aps.anl.gov>]

Folks,

 

Modbus R3-4 is now available.  These are the release notes.

 

• Added support for Modbus function 17, which is called Report Slave ID. The Modbus specification says this is only supported for serial RTU and serial ASCII communications. It reports the Run Indicator Status byte, and additional vendor defined data. Thanks to Najm us Saqib from LBNL for this.
• Added support for UDP/IP using standard port 502. The use of UDP/IP is not part of the MODBUS standard but is useful for FPGAs with Ethernet in firmware which may provide support only for UDP. The only difference between TCP and UDP operation is that when using UDP a missing reply packet is not considered to be an error until the transaction has been attempted 5 times. Thanks to Eric Norum for this.
• Added support for asynFloat64Array, which allows reading and writing 64-bit floating point arrays. Thanks to Andre (NomAnor) for this.
• Fixed absolute addressing so it only reads and writes the required number of registers. Previously it was always reading or writing the user-specified maximum number, which could cause errors if the read or write included non-existent registers. Thanks to Andre (NomAnor) for this.
• Added documentation for Modbus exceptions.

 

Home: https://github.com/epics-modules/modbus

Documentation: https://epics-modules.github.io/modbus/

 

 

Mark