Key Module Design Of Data Acquisition System Based On Embedded Linux System

The application of Embeded Linux System(ELS) has played a more and moreinportant role in the development of modern science and technology. In this paper, weconstruct a particular ELS and design an application to meet the needs of high-speeddata acquisition system (DAQ).The purpose of this paper is to control the dataacquisition card working with MPC-8536series chip as the main controller anddesigizen data transmission module and time synchronization module.In this paper, after we compared some usual ELS, choose Linux system asembeded system for DAQ. Then we configured and compiled the U-boot of Linuxsystem and kernel properly, we transplanted U-boot to the SD card,bootm the systemwith NFS or TFTP.finally, we build an environment for application. All proceduresabove gave supports to achieve a high reliability of system.According to the need of DAQ,design communication module and timesynchronization module. Firstly, the application we designed is a communicationsoftware which is used to do as a inter-medium between HW and SW using Socketnetwork programming(C/S mode) based on TCP/IP network protocol. The clientconfigures command module, data receiving&processing module and file compression&decompression module. Meanwhile, the server sets up the command analysis module,network off/on detection module, network’s transmission speed testing module and filecompression module based on Huffman coding. Second, we used IEEE-1588protocolto realize the time-accurate synchronization. In the whole testing system, we constucteda master-slave synchronization architecture and let it adjust itself according to theinformation come from packets. Results indicated that we get the desired purpose.The designing in this paper can ensured the high-speed DAQ system runningefficiently as well as guaranteed the consistency of DAQ system and external clock.