Communication with HD7279A based on McBSP serial port

The McBSP serial port of TI's series DSP devices has powerful functions and is the main way to communicate with external devices. By configuring McBSP serial port, DSP can communicate with various devices. This paper studies the method of configuring McBSP serial port as general I / O, and the connection method between HD7279A and CMU. This paper studies the interface connection method between TMS320VC5416 and HD7279A, connecting the pins CLKR2, CLKX2, FSX2 and INT3 of McBSP serial port 2 with the pins CS, CLK, DATA and KEY of HD7279A respectively. In this paper, the parameter setting and communication are realized by C language programming. Firstly, the related registers are defined by C language. Secondly, CLKR2, CLKX2, and FSX2 are set as general I / O ports. When TMS320VC5416 sends data to HD7279A, CLKX2 sends data as the CLK signal of HD7279A, and FSX2 sends corresponding data bit by bit to the DATA pin of HD7279A. In order to match the working speed of both, each bit needs 16μs delay. When TMS320VC5416 receives data, INT3 interrupt is used. The method studied in this paper has been successfully applied in a DSP I / O system composed of TMS320VC5416, HD7279A, 16 digital keys and 8 digital tubes.