The Research Of Dual Grab And Compress Card Based On CPCI Bus

After synthetical analyzing and comparing all technical schemes, this dual grab and compress card based on CPCI bus. It adopted SAA7134 to change dual analogic audio and video signals to digital audio and image data respectively. After FPGA achieved the OSD function on digital image data, it transferred the digital audio data and OSD image data to compress chip to do MPEG-2 or MPEG-4 process. Then the compressed data was transferred to CPCI bus by PCI bus interface chip PCI6140 and sent to computer. At last it was displayed by application program.At first this article introduced the whole scheme of grab and compress card, and analysed the working theory of system and the characteristic of chip, then designed four modules——audio and video grab module,OSD module,audio and video compress module and CPCI bus transfer module, and discussed carefully about function and realization of every module. Then protracted the schematic diagram, and finished the PCB designing by the anti-jamming performance and the whole lining layout. At last, it synopsized I2C bus and combined the realizing function of design, then introduced how to initialize SAA7134 by I2C bus. It synopsized some driving techonogies, and emulated the control and transfer of OSD data, and did experimental analysis.