Specify number of bytes that must be available in input buffer to generate bytes-available event
You configure BytesAvailableFcnCount to the number of bytes that must be available in the input buffer before a bytes-available event is generated.
Use the BytesAvailableFcnMode property to specify whether the bytes-available event occurs after a certain number of bytes are available or after a terminator is read.
The bytes-available event executes the callback function specified for the BytesAvailableFcn property.
You can configure BytesAvailableFcnCount only when the object is disconnected from the instrument. You disconnect an object with the fclose function. A disconnected object has a Status property value of closed.