help update server context

[Radu-0]

Hi,

I am trying to update the context of a Modbus RTU Serial Server. I am using Python 3.11 and pymodbus 3.0.0 on Windows 10.

I have started from the latest example server_async. Then I implement update_writer similar as in older update_server example.

Unfortunately, it seems that I cannot run the update_writer and serialServer in the same time.., I have tried various ways:

• Thread,
• LoopingCall from twisted,
• simply await for update_writer (the asyncio way)

Each way I tried, either the server runs either the updater.. I don't see any alternating between the 2 calls...
There are no errors or warning.. it looks like the 2 calls are waiting one for another to finish

I know there are major changes in pymodbus 3.0.0 and not sure if this is relevant.. but with Python 3.10 + pymodbus 2.5.3 + LoopingCall it worked but I am trying to move away from that config for other reasons...

Do you have any suggestions?

Thank you!

[janiversen]

You need to run the update_writer as async so that it allows other tasks to work. I hope to get around to updating the example soon.

[Radu-0]

I did exactly that...
the 2 calls were done like:

 await updating_writer(context)
server = await StartAsyncSerialServer(......

no luck :-(

[janiversen]

The first await blocks until updating_writer returns, that is not what you want, updating_writer should run as a async_task.

[janiversen]

#1176 might be of help.

[Radu-0]

Indeed 3.0.2 + using the Task did the trick! Thank you!