Abstract:TMS320VC5402 (VC5402) doesn’t have programmable non-volatile memory, so it is necessary to expand non-volatile memory for saving program codes and parameters. In many applications, this architecture makes design complex. It is a good way that DSP program codes and parameters are saved in on-chip flash memory of AVR. So, the compacted design is achieved and the disadvantages of VC5402 on control and general communication functions are compensated. On the basis of analysis on VC5402 HPI interface, hardware design of communication between ATMEL64L AVR and VC5402 HPI is provided. In the aspect of communication software design, communication protocol and DSP HPI bootloader are discussed in particular. Keywords: AVR, HPI, bootloader, DSP CLC number:TP302