The Software Design Of Synthesized Signal Source Based On Linux System

The synthesized signal source can generate a sine wave signal whose power and frequency are adjustable, and it is widely used in electronic measuring area. With the development of embedded technology, the application of the embedded system in measuring instrument is becoming a new trend, which makes instrument enriching functions, reducing the cost and volum continously. When operating instrument, user do not only need operate it in local, but also control it in remote. The remote control method based on network technology makes user controling instrument conveniently by web browser. Under this background, the development of software of synthesized signal source instrument based on embedded technology and network technology is performed in this paper.Embedded system need be controled by a processor, and S3C2440 with ARM920 t kernel produced by sam sung company has abundant hardware resources as a processor, it can meet the requirements of all functions of this instrument. Linux with opening source as a real-time operating system has been supported by many researchers, meanwhile, it can be transplanted conveniently on the S3C2440 processor.The dissertation first introduces the theory of embedded system, then describes the functions of synthesized signal source. Secondly, it introduces the development platform, including software part and hardware part, then study the process how to establish a software platform: We use S3C2440 as the CPU; for the reason of network, we choose Linux as the operating system, which is powerful in network; and choose QT which is cross-platform as the GUI libary; then we establish intercross compile environment in PC. Thirdly, for the functions of the instrument, this paper put forward the scheme of software developing. At last, according to the scheme, we realize the whole software by dividing it into several parts:1. Analysing the hardware architecture, focus on the FPGA interface part, and design a instrument driver which completes the communication between ARM and FPGA, making sure hardware can be controlled.2. Designing an application based on QT libary, and complete the control in local; build a thread which helps achieving local driver in remote control.3. Designing a dynamic web page based on Boa server, complete the remote control by cgi and socket programing.Through the above research, we complete the development of a cross-platform software in synthesized signal source which based on Linux operating system, including the Linux device driver,the object-oriented local control software and the remote control software based on Boa server.