I need know a detail about this "Circular Buffer";
Does it means that when Full, all old bytes received are overwritten (lost) to make room for newer incoming data ?


When you use flow control, when the buffer is full, it will signal to stop further communication.

I have a Com source which send data bytes endless to the TVaBuffer
and I need retrieve always the newest bytes...
I cannot stop the source.
Without use of flow control is it possible make the buffer keep the last arrived and loose the olders received ?

There is unfortunately no such function built-in.

I would suggest to implement a TVaComm buffer reader that is continuously reading VaComm and then add the functionality to make a circular buffer based on the data read at application level.
Ok, I'll try this way...
anyway I'll put this function in the features requests ;-)