Regarding point 1 - do you really mean continuous (real-time) or is it on a frequency? You might be best looking into JavaScript to run in an embedded Widget to read that data source (maybe a web socket or similar)?
Regarding point 2 - does your rs485 data need to be shown at the CMS?
Regarding point 1 - it’s continuous(real-time). How I can put this data at specific location of layout/region ?
Regarding point 2 - yes I need to show rs485 data at CMS.
#1
You would use an embedded widget which you could place in whatever Region you wanted on the layout designer.
As far as the player is concerned that data is transient - so the embedded widget connects to the data as a live stream and shows the current result.
#2
In my opinion showing real time data in the CMS is a losing battle. I think you need to look at having a server close to the data and then web sockets to pull that into the CMS somehow.
This is well outside the scope of what I can help you with and the Xibo bit is irrelevant really.
It is a JavaScript function which the Player calls when it has finished loading the page. You can do anything there that you can do in a normal webpage.