The Design Of On Board Virtue Instrument Based On Embedded Technology

The onboard instrument is the significant interface for the driver to exchange information with automobile, and it is the indispensable equipment to insure drive safely and economically. In the early time, the instruments equipped on automobile were displayed through mechanism. They have low precision, slow response, little information, and many other shortcomings. With the development of computer technology and the automobile-electron, together with the widespread application of embedded technology, the auto instrument's digitization and the multi-information synthetic display have become a developing tendency.In this paper, the embedded technology, virtual instrument technology and CAN bus technology have been applied to design, and manufacture the onboard virtue instrument. This instrument acquires the automobile working information in real-time through the intelligent data acquisition nodes of the lower computer, and transmit the data by CAN bus. Making full use of the characteristics of virtual instrument which function and parameter can define automatically, the upper computer processes the data, display the result dynamically, and emit an alarm, record and storage the abnormal condition automatically, and suggest how to deal with the abnormity urgently.The acquisition of the automobile information in working state has been studied. The information includes four types: six analog signals, such as oil quantity, voltage, oil pressure, water temperature, inside and outside temperature; switching signals, such as the door, window, etc.; impulse signals, such as car speed, and the rotate speed of engine.The data acquisition system based on CAN bus technology has been studied and designed. Several intelligent data acquisition nodes are designed and connected by CAN bus in this system, and the core processing unit obtains the data form CAN bus. The CAN bus technology having been taken in this system for data transmitting, not only for adapting to badly working circumstance better, but also for sharing the information with other net of the automobile.The virtual instrument base on PC/104 embedded computer has been designed and realized. Takes the embedded computer PC/104 as the core processing unit of upper computer, and takes the touching screen as the controlling manner for better using. The...