Abstract: An apparatus adapted to be activated by an input device for accessing a function code in a telephone comprises a first memory for storing a function code, a second memory electrically connected to the first memory for storing a datum corresponding to the function code, and an address decoder electrically connected to the input device and the second memory for decoding a signal generated from the input device and designating thereby an address to access at least one of the function code and the datum, wherein the function code stored in the first memory and the datum stored in the second memory are accessible by same the address. This apparatus effectively reduces the number of the keys required on a keypad of a telephone and is provided for a simplified operation.

Abstract: A device for detecting an operation state of a telephone hook switch in a telephone includes a timer, a controlling circuit, a counter and a table electrically interconnected. According to the present invention, the abnormal signals generated by the hook switch cannot be accepted by an exchange or even if the signals are accepted by the exchanger, the mute function of the telephone will be utilized to make the users unable to listen to each other.

Abstract: A push-button telephone dialing device for a telephone set has a push-button keypad with a plurality of keys which include a hold function key, and a telephone dialing integrated circuit including a key input signal generator wired to the push-button keypad and producing an appropriate key input signal corresponding to a key pressed on the push-button keypad. The key input signal generator produces a hold function key input signal whenever the hold function key is pressed. The telephone dialing integrated circuit further includes a speech network interrupt circuit which receives the hold function key input signal from the key input signal generator. The speech network interrupt circuit is wired to and controls the operation of a speech network of the telephone set.