Abstract: An apparatus and method for message management using nonvolatile analog signal recording and playback is disclosed. The device is an integrated circuit with interface circuitry for use as a peripheral device to a microcontroller or a microprocessor-based system. The integrated circuit is complete with differential analog inputs, auto attenuation to improve signal quality, filter, fixed references including a band gap reference, trimming, memory array, multiple closed loop sample and hold circuits, column device, row decoder, address counters, master oscillator, chip function timing circuits, and a serial peripheral interface (SPI) and circuits on a single chip. The integrated circuit is interfaced with a host microcontroller through the SPI. The host microcontroller can send a number of commands to the integrated circuit through the SPI for efficient message management. These commands include the basic commands to record or playback and various addressing and message cueing options.

Abstract: Message management methods and apparatus for the storage and selective playback, erase and other manipulation of messages such as voice messages in a voice message system are disclosed. The devices of the invention include analog signal sample and analog storage capabilities whereby messages may be stored in one or more message segment storage locations. A register stack in each device keeps track of the message number associated with the message segment stored in the respective message segment location so that message segments associated with a particular message may be located in sequence for seamless playback of the entire message. Message segment storage locations available for storing new messages may be identified by a flag identifying the same, such as by an otherwise unused message number stored in the associated stack register. Each device includes the capability of cascading with identical devices so as to extend the total record and playback time available.