In today’s highly information-based society, information and communication have become the lifeblood of modern society. As means or manners of information transmission and communication, computer integrated communication has became a powerful driving force in twenty-first century.And in nowadays, modem play an important role in communication.
This paper introduces a AT89S52-based approach to achieve FSK modem. The article first chapter introduces the background and the subject of the main elements of the design; the second chapter describes the overall design of the program; In the third chapter, it introduces the design of hardware circuit with AT89S52; In the forth chapter, it describes the results of the design of system debugging. Finally, sum up this design.