Embedded Ip-based Audio System Design And Realization

With the rapid development and wide application of embedded technology and network technology, audio system which combines two kinds of advantages well is being researched and exploited continuously. With the audio data acquisition and play instrument which is carried out by the traditional SCM is being digitally transformed and network reconstruction, the development of the intelligent audio terminals which involve the new embedded technology and information network technology has become a hot issue.Under this background, embedded audio system based on the IP network is researched. In embedded system design scheme, S3C2440 processor and the Linux operating system are chosen. In hardware design scheme, the requirements of system hardware resources are analyzed and S3C2440 microprocessor and developboard which are used by the project are introduced. In software design scheme, embedded Linux software development platform is built. In driver design scheme, the mechanism of audio device driver and Ethernet controller driver are fully discussed. DMA technology and multi-buffer are used to enhance the system performance and to satisfy the audio frequency-timely request. The realization of the applications is based on multithreading mechanism, which is also fully discussed in this paper. In order to ensure the data transmission accurately and orderly, the socket communication technology based on TCP/IP protocol is adopted. The audio system comprises the client and the server. The server is the demo board with a single ARM CPU, which supports multi-user, multithreading. Application program combination of audio sampling, transmission, processing and MP3 decoder as an example to demonstrate the performance on the platform is developed. At the end of the paper, the functions of the system are tested.Test results show that audio system has software transplantability and stability, and has data communication transmission reliability, function of network monitoring is available. The embedded audio system can be used in MP3,mobile phones, audio on-demand and so on. It has a high value of application.