The Design Of Inclination Measurement System Based On ARM9

With the rapid development of embedded technology, the embedded system is widely used in various fields, which mainly include the industrial control, data acquisition, transmission, communication and so on. The embedded system centers on application and is highly specialized, and it is cuttable in software and hardware for different practical situation. At the same time, embedded real-time operating system is very demanding on Real-time, reliability and power consumption. In the digital age, with its superior performance, the embedded system will be more widely applied in all aspects of life.Inclination measurement is a technology specifically used to measure the gradient of the object relative to the horizontal, which can be seen everywhere in the practical application. Now the more common angle measuring instruments mainly take the single chip microcomputer as control core, but the data processing capability of MCU is very weak, and it is unable to handle complex mathematical operation quickly thus influent the sampling frequency. Further more, for its own condition, the MCU cannot achieve personalized and complicated system. So it can not well adapt to the development of some areas such as the railway system, the automobile industry and military automation. While embedded processor has strong data processing ability, and can run embedded operating system. It has obvious advantages in data acquisition field and achieving personalized and complicated system.This paper designs a kind of inclination measurement system based on ARM9 processor S3C2440. This system can measure the spatial gradient of an object, and can display the angle value and the angle variation curves in a period of time in real-time on the touch screen. The hardware design mainly contains control module and data acquisition module. The control module is composed of a S3C2440 processor, Nand Flash memory, SDRAM memory, JTAG interface, clock circuit, reset circuit, power supply circuit and touch screen, the data acquisition module is composed of the application circuit of a three-axis accelerometer MMA8451 Q. System software design mainly consists of U-Boot, Linux kernel, YAFFS2 file system, MMA8451 Q character device and Qt application program. The system first reads data from the character device file of MMA8451 Q by the Qt application program. Then the angle is got after the date is processed by the inclination measurement algorithm. Finally, the system shows the value and the variation curves of the inclination in the embedded graphical user interface(GUI). Experiments demonstrate that the inclination measurement system can get a tilt every 500 ms, and draw the angle variation curve in 10 s.