9.2.5.6 Raw Binary - From DTE to DCE

For transmission of data in the Binary mode the DTE must either specify the number of bytes it wishes to send to the DCE or specify zero to request a persistent exit from the Terminal mode. On leaving terminal mode, the DCE will accept binary format data until such time as:

1. The ‘+++’ escape sequence is received from the DTE
2. The number of bytes requested by the DTE has been sent

When operating in non-terminal mode, the DCE will periodically flush (in other words, transmit) the accumulated data. Generally, this means writing the data to an associated socket. The time period for the automatic flush of data is configurable (please see the XXX command).