Description: If this switch is active (2), the serial buffer is flushed each time a new connection is opened; any residual data which could not be sent (e.g., handshake stop of the serial terminal device) are therefore lost. But if you connect a terminal device to the Com-Server which for example requires a longer handshake, you can prevent flushing of the buffer by deactivating the switch (1). Then several connections can be opened in turn on the network side and the data are accumulated in the buffer until they are sent.