Abstract: In a multi-line telephone system, an improved method is provided for automatically detecting and indicating the status of each of a plurality of telephone lines despite variations in battery voltages on the line or lines and without requiring any adjustments by the user. Each of the lines in a system can be polled sequentially or individually as desired. The improved method measures the present voltage level associated with the selected line, distinguishes the condition of on-or-off hook or on-hold from other possible states, compares and processes the present measured voltage level in a state matrix, and updates the status indication of the selected telephone line accordingly. Status conditions which are detected and indicated by this method include on-hook, off-hook, and on-hold.

Abstract: A method of establishing communications between a first communication station and a second communication station comprising the steps of: storing a communication originate packet in the first station; storing a communication answer packet responsive to the originate packet in the second station; transmitting the originate packet to the second station from the first station; detecting the originate packet in the second station; transmitting the answer packet from the second station to the first station upon receipt of some but not all of the originate packet; and, establishing communications between the first and second station in response to receipt by the first station of the answer packet.