The Industrial Raspberry Pi Forum

Hi There,

Is there a way to limit the amount of times (for example, write only once) to a register or coil?

From what I can see, listing a write register in 'extended data' will keep writing to the register(s) on a interval based on the 'Action Interval'.

We have have a few registers on a field device which only have a limit number of writes and after a while the flash memory will break.

Thank you,
Chris

Hi Chris,

It is not possible to write only once with piModbusMaster.
For this however you can directly access the libmodbus API from another application on startup for making needed initialisiation and thereafter start piModbusMaster service.

LibModbus

Regards

Johannes