基于单片机的电压频率监测系统设计本科学位论文.doc

基于单片机的电压频率监测系统设计

目录

摘要 ................................................................................................................................I

Abstract..........................................................................................................................II

第一章 绪论..................................................................................................................1

1.1 问题的提出......................................................................................................1

1.2 设计的意义.....................................................................................................1

2.1.2 电压测量方法.....................................................................................10

2.1.2.1 A/D 转换法..............................................................................10

2.1.2.2 V/F 转换法...............................................................................14

2.2 方案选择........................................................................................................16

2.3 系统框图........................................................................................................17

第三章 系统硬件电路的设计....................................................................................17

3.1 单片机处理控制电路...................................................................................18

3.2 频率信号预处理电路...................................................................................20

3.2.1 小信号放大电路.................................................................................20

3.2.2 整形电路.............................................................................................21

3.7.3 指令描述............................................................................................31

3.7.4 接口时序说明....................................................................................33

3.8 电源电路的设计...........................................................................................35

3.9 串口通信电路...............................................................................................37

第四章 系统控制软件设计........................................................................................41

4.1 系统软件框图................................................................................................41

4.2 频率测量子流程图.......................................................................................42

4.3 A/D 转换子流程图........................................................................................44

4.4 显示子程序...................................................................................................45

4.5 延时子程序....................................................................................................46

参考文献......................................................................................................................51

中英文翻译..................................................................................................................52

总结体会......................................................................................................................53

致谢..............................................................................................................................55

附录..............................................................................................................................56

图目录

图 2. 6 多周期同步测量法的流程图...........................................................................7

图 2. 7 直接测频率测频原理图...................................................................................8

图 2. 8 计数法设计软件流程图...................................................................................8

图 2. 9 直接测频法原理框图.......................................................................................9

图 2. 10 三位并行 A/D 转换器原理图........................................................................10

图 2. 11 逐次逼近型 A/D 转换器的工作原理图.......................................................12

图 2. 12 双积分型 AD 转换器的框图.......................................................................13

图 2. 13 双积分 AD 转换器波形图...........................................................................14

图 2. 14 施密特触发器型压控振荡器的原理性电路和电压波形...........................15

图 2. 15 电容交叉充、放电型压控振荡器的原理图...............................................15

图 3. 5 整形电路..........................................................................................................23

图 3. 6 施密特触发器对波形整形的原理图..............................................................23

图 3. 7 ADC0809 芯片管脚图.......................................................................................24

图 3. 8 ADC0809 内部结构图 .....................................................................................25

图 3. 9 X25045 引脚图................................................................................................27

图 3. 10 X25045 看门狗电路硬件连接图..................................................................28

图 3. 11 晶振电路.......................................................................................................29

图 3. 12 显示电路........................................................................................................29

图 3. 13 LCD 管脚图....................................................................................................30

图 3. 14 读操作时序...................................................................................................33

图 3. 21 MAX232 的引脚图..........................................................................................39

图 4. 1 系统总流程图..................................................................................................41

图 4. 2 频率测量子流程图..........................................................................................43

图 4. 3 A/D 转换子流程图..........................................................................................44

图 4. 4 显示流程图.....................................................................................................46

图 5. 1 原理波形图.....................................................................................................49

表 3.4 LCD 接口说明表................................................................................................30

表 3.5 RAM 地址映像表.............................................................................................32

表 3.5 LCD 接口时序表..............................................................................................34

表 3.6 RS-232C 接口信号表.......................................................................................38

表 5.1 相对误差...........................................................................................................49

With digital informatization in the rapid development of all walks of life,

industrial system of informatization, digital will also become the future trend of

development. Especially in the narrow space when operating, often face many

functions, sizes, different range instrument panel. These instrument panel not only

occupy a space, and not enough intuitive, easy to cause the working staff of the

incorrect operation or reaction lag, give operating cause unnecessary trouble. So using

AC frequency and voltage measurement technology, design the voltage frequency

monitoring system, may simplify system operation space, improve work efficiency.

AD0809；