Abstract: An example of using dual RAM device in the software and hardware design of data interface module is introduced in this paper.The module selects the VME bus,and adopts a DSP chip with powerful operation capability,a dual RAM with easy memory ability,a difference interface module and a DC/DC voltage convertor.The structural features of the dual RAM CY7C026-25AI and its fantastic work method called Ping-Pang are explained.And the differences between the performances of dual RAM,FIFO and some normal memorizers are analyzed.A new concept about the cooperation method between SHARC processor and FIFO chip,that is the Combination Method,is proposed.The absolute advantage of the dual RAM device in the modern data acquisition implementors has been clearly demonstrated.