摘要 |
<p>A telecommunications system with a call waiting feature, comprises a central office and a plurality of subscribers. The system includes an arrangement for transmitting a signal over an off-hook line to alert the subscriber to the presence of an incoming call, and a cancel call waiting (CCW) register at the central office. The CCW register is associated with each subscriber line and is set to cancel the call waiting feature in response to receipt of a cancellation code over the associated subscriber line and is reset upon termination of a subsequent call. The central office further comprises a delayed cancel call waiting (DCCW) register for each subscriber line with at least a first state and a second state. The DCCW register is set to the first state in response to receipt of a DCCW access code transmitted over its associated subscriber line. An arrangement is provided for checking and resetting the state of said DCCW register when the associated line goes off hook in response to an incoming call. The CCW register is set in response to detection of a first state condition in the DCCW register so as to cancel the call waiting feature only for the duration of a single incoming call.</p> |