本文介紹了汽車行駛過程中速度參數的測量原理，建立了相關數學模型。并設計了
采用以嵌入式微處理器MC9S12DP256B 為核心的智能數字式汽車組合儀表解決方案，具有實時性好、反應靈敏、精度高等優點。系統可對汽車的車速參數進行實時測量和顯示，并具有安全報警功能。系統還預留了SCI 和CAN 總線接口，便于與汽車其他電子控制系統聯接通信功能的擴展。
關鍵詞：速度測量 周期測量安全報警
Abstract: The principle of how to measure the main automobile running parameters is discussed in this paper and the correlative math model is given. And design a high reliability aptitude instrument solution project of which the core is that the embed microprocessors based on MC9S12DP256B are used is invented. This project has some advantages, such as good real time, high design degree, and high sensitivity to response. Using this instrument, the real time measure and display the parameter of vehicle speed can easily be made. The bus interface of I2C and CAN is obligated in this instrument system. The aim of doing this is to make this system can easily expand system function and can connect and communicate with other automobile electrical control system.
Key words: speed measurement；cycle measurement；Safety alarm