Linux Real Time and CODESYS Virtual Control

Hi,

I have already CODESYS Virtual Control for LINUX running and I am able to run virtual slaves for modbus RTU.
Wago CC100 is the master device.
I am using a USB hub where I have 4 converters USB to RS485.
I know USB has a delay, I mean, it is not real time.

After installing the RT Linux image, I am not able to communicate with slaves anymore.
It seems Codesys Modbus Driver I/O is not running.

Can someone help out to figure out what might be going on?

Is there any documentation explaining how to set up a Real Time linux with CODESYS Virtual Control?

Thanks in advance.

Cheers.