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Modbus universal

Posted: 20 Jul 2024, 18:58
by Smotek7
Hi,
a year ago the idea was to create a Modbus universal plugin.
I was looking for some info, but I couldn't find it.
What is the current status?

The thought occurred to me whether it wouldn't be easier not to make it completely universal. But take some existing one and add devices and registries to it.
For example SDMxxx. Devices are selected there and registers are changed accordingly.
Basically, it's a controlled addition of Modbus devices to the list.
What do you think about it?

Re: Modbus universal

Posted: 20 Jul 2024, 20:06
by TD-er
The SDM/Eastron plugin is already using the new idea I have for managing the shared modbus among several plugins/tasks.

What this Eastron plugin does is it is scheduling a list of registers (and modbus addresses) to query and then process this list plus store the result on the appropriate task output.
This approach has as big advantage that you're not waiting for a reply but just periodically check if there is a reply.

However this right now only does work when performing lots of reads.
When you also want to write inbetween, you need to make sure this is put to the front of the list and maybe also claim a time slot where no other calls are being made inbetween.

So I want to implement this "modbus manager" first before I can make such a generic plugin (or simply add modbus commands to be called from rules)

Re: Modbus universal

Posted: 20 Jul 2024, 20:39
by Smotek7
Oh yeah
in other words, you work on it after small steps.
Thank you for the info.