The control modes for RTS are:
The Enable and Disable control modes affect RTS processing during a First Level Open. When these control modes are set using IOCtl ASYNC_SETDCBINFO, the value of the RTS signal can be immediately modified by the physical device driver. The action depends on the previous control mode of RTS and the current value of the RTS modem control signal. If the control mode of RTS is Input Handshaking, the device driver controls the RTS signal, depending on how full the receive queue is. If the control mode of RTS is Toggling on Transmit, then the physical device driver controls the RTS signal, depending on whether it is transmitting data. The bits that control these states of the physical device driver are in the device control block.
Initial Value