Taking OMAPL138 as the hardware platform, using DSPLINK driver module, a mechanism that could be used to communicate between ARM and DSP was designed. On one hand, in ARM side, LINUX operating system was run to deal with humancomputer interaction. On the other hand, in DSP side, two levels cache was built to circularly store data coming from the ARM side and to ensure that the cache had data available for DSP to acquire and calculate. Moreover, for the large amount of transmission data, the mode that ARM directly read from and wrote to DSP RAM was selected, which would improve the communication speed between the two cores.The design has been proved to run stably and reliably.