Abstract: A wireless communication device having an accessory port and a processor to detect when an external accessory is coupled to the accessory port, and then identify the type of external accessory. A data line connects the external accessory to the wireless communication device, the data line being a portion of a pulse code modulation (PCM) port in the accessory port. The processor senses activity on this data line, including a signal transmitted by the external accessory indicative of when the external accessory is coupled to the wireless communication device. The processor further senses identification data associated with the external accessory, with the identification data including an identification code of the external accessory. The processor generates a clock signal, and the external accessory transmits the identification data to the wireless communication device over the data line in response to the clock signal. In this fashion, the processor repeatedly senses the transmitted identification data.

Abstract: A method and apparatus for communicating both voice and control data between a communication device (such as a cellular phone) and an external accessory (such as a hands-free kit) over a data bus. The method includes formatting a sequence of bits into a repeating sequence of first time slots and second time slots, transmitting the voice data in the first time slot, and transmitting the control data in the second time slot. Notably, a first bit of each of the second time slots comprises a clock bit that alternates between a high value and a low value (e.g. a ‘1’ or a ‘0’) as between consecutive second time slots.

Abstract: A microprocessor controlled system is provided which is responsive to displacement information such as rotation rate and position of a rotary knob for controlling instrument functions such as display scrolling, the setting and display of measurement conditions (operating parameters), and the entering and display of alphanumeric data.