Ready condition

The ready condition is an important property of any serial port. The COM port server transmits no data between the serial port and the network if the status is not "ready". Apart from that, in the client mode the act of switching between the "ready" and "not-ready" states is used to establish and terminate TCP connections. The readiness of the port can be checked in two different ways. In DTR mode (default) only the DTR handshake is monitored. The serial interface is considered to be ready for as long as the DTR line is active. In data mode, the serial interface is considered to be active for as long as it receives data. If no data is received during the timeout period, the port reverts to its "not ready" state.