分类号：TP271 U D C：D10621-408-(2008)2945-0 密 级：公 开 编 号：2004051149
成都信息工程学院
学位论文
二维高精度液晶显示电子指南针
论文作者姓名： 申请学位专业： 申请学位类别： 指导教师姓名（职称）：
李 杨 电子科学与技术
工学学士 侯俊勇（副教授）
论文提交日期： 2008年6月10日
二维高精度液晶显示电子指南针
摘 要
由于早期的指南针采用了磁化指针和方位盘的组合方式，整个指南针从便携性、指示灵敏度上都有一定的缺陷。采用专用的磁场传感器结合高速微控制器（MCU）的电子指南针能有效解决这些问题。
所设计的系统采用了磁阻（GMR）传感器采集某一方向磁场强度后通过MCU控制器对其进行判断后将处理的结果，通过LCD显示屏显示出来，并能够通过MCU的串口发送给上位机。实际测试指南针模块精度达到1°，能够在LCD上显示当前方位并能通过键盘有选择性的上传指南针处理得到的数据。
关键词：指南针 GMR MCU LCD
The design of electronic compass
Abstract
Since the early use of a magnetic compass and direction-pointer of the composition, the entire compass from scratch, on the instructions of a certain sensitivity of the defect. Using a dedicated high-speed magnetic sensors with microcontroller (MCU) electronic compass can effectively solve these problems.
The system is designed by the reluctance (GMR) sensors collecting a certain direction through the magnetic field strength after the MCU Controller its judgement will be dealt with the results, through the LCD screen display and can be sent to the MCU's top serial Machine. The actual test compass module can reach 1 °, in the LCD display on the current position of the keyboard and through selective compass upload the data processing.
Key words: compass; GMR; MCU; LCD
目 录
论文总页数：23页
1 引言 .............................................................................................................................................. 1 1.1 课题背景 ................................................................................................................................ 1 1.2 国内外研究现状 .................................................................................................................... 1 1.3 本课题研究的意义 ................................................................................................................ 1 2 系统框图及原理 ........................................................................................................................... 1 3 磁场信号采集和处理 ................................................................................................................... 2 3.1 磁阻传感器 ............................................................................................................................ 3 3.2 磁场测量ASIC...................................................................................................................... 3 4 系统硬件....................................................................................................................................... 5 4.1系统控制器 ............................................................................................................................. 5 4.1.1 控制器内部结构 ............................................................................................................. 5 4.1.2 控制器存储结构 ............................................................................................................. 5 4.1.3 控制器具体电路 ............................................................................................................. 6 4.2 系统扩展电路 ........................................................................................................................ 7 4.2.1通信电路 .......................................................................................................................... 7 4.2.2 指南针模块接口电路 ..................................................................................................... 8 4.2.3 实时时钟电路 ................................................................................................................. 9 4.2.4 液晶显示电路 ............................................................................................................... 10 4.2.5系统输入电路 ................................................................................................................ 10 5 系统软件..................................................................................................................................... 12 5.1 主监控程序 .......................................................................................................................... 12 5.2 实时时钟驱动 ...................................................................................................................... 13 5.3 人机界面驱动 ...................................................................................................................... 13 5.3.1 液晶模块驱动 ............................................................................................................... 14 5.3.2 键盘驱动 ....................................................................................................................... 14 5.4 指南针模块驱动 .................................................................................................................. 14 结 论......................................................................................................................................... 16 参考文献......................................................................................................................................... 17 致 谢......................................................................................................................................... 18 声 明........................................................................................................................ 19
