Need help with SDK and "Ref In"

Hello.

Help than you can.
In the examples, no matter what I need.
The documentation is not so easy to understand.
How can I use "Ref In" connector for synchronized output?

At the same SDI(HDMI, ...) input may not be available(not connected, only sync).
As can be determined that the "Ref In" is connected and using an external sync?
There are some examples?

Thanks.

A Blackmagic sync generator can be used
I am not allowed to post urls on this forum so you will have to search for this

Thanks, I checked, "Ref In" works.

Indeed it does! Thanks!