基于MSP430单片机pH值测量仪的设计(附电路原理图,程序代码)

基于MSP430单片机pH值测量仪的设计(附电路原理图,程序代码)(论文12000字,外文翻译,原理图,程序代码)
摘要：如今生产、生活的许多方面都离不开pH的测量与控制，pH的测定在电力、化工、医药和环保等部门被广泛应用。本论文旨在介绍一种基于MSP430单片机的pH测量仪的设计。本设计通过电位法测量液体pH值，首先对pH传感器采集的电压信号进行放大，再传入单片机内部进行A/D转换，经过程序算法得到精确的pH值。将由温度传感器采集到的温度信号传入单片机进行进制转换，并通过液晶显示出来。考虑到由于温度变化带来的pH测量误差，故在设计中加入温度补偿校正，使其能够更加准确地监测液体的pH。
关键字: MSP430；pH测量；液晶显示；温度补偿；电位法

The design of a measuring instrument for pH value based on MSP430 microcontroller
Abstract: Today, many aspects of productionand life depend on the measurement and control of pH value.pH measurement is widely used in power, chemical, medicine and environmental protection departments.The purpose of this paper is to introduce the design of a pH measuring instrument based on MSP430 microcontroller. This design measured the pH value of liquid by the electric potential method.The voltage signalcollected by the pH sensor was first amplified, then transferred to the internal A/D conversion ofMCU, and through the program algorithm, accurate pH value was obtained.The temperature signal was collected through temperature sensor, thentransferred to microcomputer to realize hexadecimal conversion, and displayed through the liquid crystal display.Taking into account the pH measurement error caused by temperature changes, the temperature compensation is added in the design, so that it can monitor the pH value of the liquid more accurately.
Keywords: MSP430; measurement of pH; the liquid crystal display; temperature compensation; potential method
 

目录
1 系统方案    3
1.1 系统设计背景及意义    3
1.2 方案论证    3
1.2.1 pH测量方法的选择    3
1.2.2 pH电极传感器材质的选择    3
2 pH测量仪的检测原理    4
2.1 电位法测量原理及温度补偿    5
2.1.1 电位法原理    5
2.1.2 温度补偿    6
2.2 两点法标定    6
2.2.1 标准溶液的选择    6
2.2.2 标定方法    7
3 硬件设计    7
3.1 系统硬件设计    7
3.2 单片机主芯片    8
3.2.1 MSP430F149单片机特点    9
3.2.2 MSP430F149单片机最小系统    9
3.3 pH传感器模块    10
3.4 温度传感器模块    11
3.5 运放模块    13
3.6 A/D转换模块    13
3.7 液晶显示模块    15
3.8 硬件误差降低措施    16
4 软件设计    17
4.1 IAR C430应用    17
4.2 程序流程图    18
4.2.1 主程序流程图    18
4.2.2 子程序流程图    19
4.3 单片机内部存储    20
5 实验数据和结果    21
5.1 实验过程及数据    21
5.2 误差分析及应对    24
6 总结    25
参考文献    25
致谢    27
附录1：整体电路图    28
附录2 :系统主程序    29