Asynchronous register reading

[dejan]

Hi Mikhail,

I know that device can be polled asynchronously (output channel with command type “Request”), but what I want is to read just one specific register at a time, not all registers defined by device template. Besides, I need to read different registers this way. I’m asking this because in the machine I work with there is a log memory, accessible through Modbus function “Read input registers”. Every log record is 8 registers long (16 bytes) and there are 256 such log records. First log record starts at address 0, the second starts at address 8, and the last one starts at address 2040. My idea is to write a small program that will send requests to Scada Server through TCP. Each successive request should read the next log record. Reading stops when all new records are read. Is there a method from ServerComm class that could be used for this task – reading a number of successive registers, with programmatically defined starting address?

Thanks,
Dejan

[Mikhail]

Hi Dejan,
In the similar situation I wrote a driver that uses the existing Modbus classes.
You may need this article about drivers development and this solution as an example. Use Modbus class for accessing your device.
Follow up questions please post in Development and Integration

[Author]

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