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<== Date ==> <== Thread ==>

Subject: Modbus Polling disable/enable
From: "[email protected]" <[email protected]>
To: "[email protected]" <[email protected]>
Date: Thu, 6 Sep 2018 09:15:55 +0000
Hello Tech-talk


I'm currently working in a module which relies on the modbus module and I need to create a button in the user

interface that allows to disable the read polling.

As it is working now, readPoller still reads the values even if the associated record is disabled.


I found two ways of achieving the goal:

    1. Set pollMsec  to a value less or equal to 0 and add an extra record for each register that has periodic scan and writes to MODBUS_READ (disable button would disable this record)

    2. Use absolute addressing (modbusStartAddress=-1) and change all the records to be periodic scanned


The downside of the first solution is that I need to have double records for each modbus register.

The downside of the second solution is that this might be a feature of absolute addressing that might change, as documentation

is not explicit on the point that absolute addressing mode disables the readPoller thread and calls doModbusIO on record's demand.


My question is:  what is the recommended way?


Best regards and thank you,

Emilio

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Replies:
RE: Modbus Polling disable/enable Mark Rivers

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