毕业设计-基于AT89C51单片机的心率计的设计.doc

安徽机电职业技术学院 毕业论文 基于AT89C51单片机的心率计设计 系 别 电 气 工 程 系 专 业 应用电子技术 班 级 电子3101 姓 名 张 燕 学 号 1301103021 指导教师 黄 鹏 2012 ～ 2013 学年第 一 学期 摘要心率一般是指人一分钟心跳的次数，它是反映人体循环系统机能的重要参数，因此，对心率进行测量，在临床上具有重要的意义。 论文首先介绍了心率计系统的基本原理，接着确定了设计方案。设计方案以单片机为核心，还包括LED显示电路模块、传感器整形放大电路。阐述了软硬件方面心率计系统开发的整个过程以及相关的技术问题。本系统硬件部分采用压电陶瓷传感器，将人微弱的脉搏信号转换为电脉冲信号，确定用AT89C51单片机对电脉冲信号进行计数，用8155芯片扩展I/O口并作为LED显示接口，并用74LS244缓冲器提高驱动。软件部分用汇编语言对单片机进行编程，主要实现了定时、计数中断以及字型码转换。软硬件调试成功，系统运行正常，能较准确地测量人的一分钟心率值。 关键词：心率AT89C51单片机传感器LED显示器 microcontroller Abstract The heart rate generally means peoples heart beating times in one minute. It is the important parameter that reflects the human body circulatory system function, therefore carrying on accurate diagraph to the heart rate has the great significance on the clinic. The thesis introduced the basic principle of the heart rate counts system first, and then has determined the design proposal. The design proposal takes the monolithic integrated circuit as a core, but also includes the LED display circuit module, the sensor reshaping enlargement electric circuit. It elaborated the entire development process from the software and hardware aspect of the heart rate counting system, as well as the correlation technical question. This system hardware segment uses the piezoelectricity ceramics sensor which transforms the person’s weak pulse signal into the electrical pulse signal. It counts the electrical pulse signal by the AT89C51 monolithic integrated circuit. The system uses 8155 chips, the expanding I/O port, as the LED display connection port, and the 74LS244 buffer enhances the driving electric voltage. Software segment carries on the programming with the assembly language to the monolithic integrated circuit, mainly realized, and has fixed time counted the sever