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 parallel analog-to-digital ("A/D") converter utilizing only N comparators and at least N-1 summing networks made of the simple resistance elements. The A/D conversion process operates asynchronously without need for registers, a clock circuit or latches and determines at a high rate of speed the N output bits for a given analog input signal. Each of the summing networks produces a composite analog signal which is fed into a respective one of the comparators. The digital output bit produced by each comparator is fed into the summing networks associated with those comparators whose output bits are less significant. Accordingly, when all output bits are changing on account of a new analog input value, the converter determines the most significant bit first, the next most significant bit next, and so on, until the least significant bit is determined.