The MS87V1021 is a single chip recording and playback IC that is controlled by the microcontroller in serial mode, compresses voice with the 4-bit OKI ADPCM algorithm or 4-bit OKI ADPCM2 algorithm with high tone quality, and has 2-Mbit DRAM in which recorded data is stored and 512-Kbit mask ROM in which fixed messages reside. The MS87V1021 includes such features as Normal Recording and Playback, Delayed playback, Retroactive playback, Fast forwarding, and Rewinding. The internal memory in which voice data is stored allows a recording/playback system to be constructed merely by externally connecting it to a microphone, a speaker driving amplifier, and a speaker.