VFD Automobile's Digital Gauge And Autobody Control System

The dissertation aims at a VFD automobile's digital gauge and autobody control system, in which the hardware and software are included. The Microcontroller Unit PIC16C73 of Microchip Company is used as the main controller of the system. The hardware system is composed of control circuit, power circuit, detection circuit of input signal, relay control circuit, distance memory circuit, and VFD gauge circuit is also given. The idea of modularized design is adapted in the software system, the physical layer and the application layer are included in the software system:. In the physical layer the basic functions of the system are realized by the digital inputs module, interruption module, A/D module, gauge's button input module, relays controlling output module, gauge displaying output module and 24C02 operation module. The application layer includes initialization module, main program module, 0.5s timing module and interruption module. The timing and interruption mode is used to trigger tasks. The initialization module initializes the system and sets the interruption. The main program module is a circulation of clearing watchdog and outputing the controlling data of relays. In the 0.5s timing module, the system calculation is done , gauge display and relay output are refreshed and A/D signal is also measured. The interruption module fulfills the speed detection, A/D detection and distance calculation. It detects the digital inputs at an interval of 30ms. The security and reliability of the system are greatly improved because the anti-interference of both hardware and software are taken into account. In the end of the dissertation, a set of VFD automobile's digital gauge and autobody control system is developed and tested. Experiments show that it meets the demand of vendor in precision and it has good performance and stability.