Arm And Arm Linux-based Car Drive Recorder Analysis And Design

The vehicle traveling data recorder, also named vehicle black box is an electronic device installed in a vehicle. It used for monitoring, recording and saving various states and data in vehicle traveling, such as the speed, time and distance. It also can output the traveling data via its interface in order to provide reliable and accurate scientific basis for analyzing and judging the vehicle's state in dealing with the traffic accident. The task is set by the project that is funded by the Electronic Development Fund of the Ministry of Information Industry (MII) of the PRC.China. Compare to the similar products, it adds the function of video and audio. The completed project has been checked and accepted by the MII.This thesis introduces a solution to the vehicle traveling data recorder based on ARM and ARM Linux which is low cost and highly extensible. The system as the main controller module in the project funded by MII implements the standard functions of the vehicle traveling data recorder. In hardware aspect, the thesis analyzes the key functions of the vehicle traveling data recorder and the corresponding design of peripheral circuits within ARM chip with special apparatus. While in the software aspect, it analyzes the high usability of the embedded software platform based on YAFFS file system and Linux with kernel version 2.6. The analysis covers the features and main principle of YAFFS, the implement mechanism of Linux thread, the improvements on the response time of Linux kernel 2.6, and more. The thesis also gives the main points, the program flows and main data structures in the design of the recorder's application which based on Linux multi-thread programming.For extension, we add a DSP module to the vehicle traveling data recorder used for collecting the video and audio data. The DSP in this module is TI DM642, a high-performance digital media processor which is optimized for video. The DSP module collects three channels video signals and compresses them with the algorithm which can be one of the follows: MPEG-2, MPEG-4, H.263, H.264 and more. The thesis discusses the basic principle of the implementation of video and audio function, memory organization of DSP module, communication between ARM and DSP and some considerations on practical progress.