A port is considered hung when it refuses to accept keyboard input and is producing no new terminal output.
In the majority of cases, a hung port occurs due to an x-off signal being sent to the device. It is advisable to try an x-on before any other remedies.
The reset-async, reset-port, and reset-user commands can be used to clear some hung port conditions.
The logoff command is provided to force a hung port to the logon prompt. The last resort is rebooting the system.