Key Technologies Embedded Digital Mixer

Based on embedded platform digital audio equipment with high performance price ratio, low power consumption, high integration, high scalable capacity, and rapid development speed, etc. is paid more attention to by many countries all over the world. Therefore, the fantastic development embedded technology, which is developing to apply the digital mixer, makes it modular, networking and intelligent, having widespread practical value and immense practical significance.In view of this kind of demand, this paper has proposed embedded digital mixer solution which based on embedded ARM processor and FPGA structure. According to above, hardware circuit of the mixer has been designed and signal processing to the input audios has been given. This paper has designed a digital mixer with high quality, low cost and user-friendly interface which meets the various situations needs completely. In the topic, the ARM processor uses Samsung's S3C2440A, FPGA uses Xilinx's XC3S500E. The paper primary coverage is:1. Hardware design and debugging of embedded digital mixer include circuit schematics and PCBs. These hardware circuit schematics includes: audio analog-digital /digital-analog conversions and their peripheral circuits, equipment to connect with the outside world, and ARM and FPGA hardware circuit diagram.2. In has thoroughly studied of the Linux driver, give the development environment which has built on the Linux OS, and use the hardware platform to debug the SPI interface, A/D converter drivers.3. Audio signals implementation signal processing design and simulation in the FPGA. At Xilinx ISE10.1 using Verilog HDL designed adjustable gain digital audio mixing, audio ADPCM codec, and calculated eight channels'audio correlation coefficient. Through the Xilinx's reference design implemented digital audio asynchronous sample rate conversion. These programs have carried out simulation and synthesis at ISE10.1, finall has implemented in the development board successfully.