时钟计时器的设计（毕业设计）.zip

摘 要



时钟计时器要求用单片机及6位LED数码管显示时、分、秒，以24（小）时计时方式运行，能整点提醒（短蜂鸣，次数代表整点时间），使用按键开关可实现时、分调整，秒表/时钟功能转换，省电（关闭显示）及定时设定提醒（蜂鸣器）等功能。本设计大体思路是：采用独立式按键进行时间调整，六位数码管动态扫描的显示方法。其中AT89C52是核心元件，同时采用数码管LED动态显示“时”，“分”，“秒”。与传统机械表相比，时钟计时器具有走时精确,显示直观等特点。它的计时周期为24小时，显满刻度为“23时59分59秒”，另外具有校时功能等特点。该系统同时具有硬件设计简单、工作稳定性高、价格低廉等优点。

本设计中各功能的具体实现主要从硬件和软件两部分入手。硬件部分：对硬件电路进行模块化设计，其中时钟接口电路为单片机及整个硬件电路的工作提供统一的工作频率；复位电路保证了系统可以有固定的初始状态；LED显示电路在视觉上直观地显示软硬件电路所达到的效果，用74LS244作为AT89C52的线驱动，用三极管9012作电源驱动输出，以提供共阳LED数码管的列扫描驱动电压；蜂鸣器电路在对系统的操作时有听觉上的明确提示；按键电路实现对时钟计时器的各功能间切换；电源电路提供系统的工作电压，并分别给出各部分设计电路图。软件部分：根据设计要求功能设计程序，包括主程序及显示子程序；用于时间计时的定时器T0中断服务程序；用于指示时间调整单元数字的闪亮或秒表计数的定时器T1中断服务程序，调时功腀@绦颍氡砉δ@@绦颍种邮奔渖瓒üδ@@绦虻雀髯映绦颉�



关键词：AT89C52 LED显示 74LS244















Abstract



Clock timer asked to use SCM and six LED digital display hours, minutes, seconds, to 24 (small), the run time, to remind the whole point (short beep, the number of representatives of the whole time), using key switches can be realized hour, minute adjustments, stopwatch / clock function of conversion, energy saving (turn off the display) and the time set reminders (buzzer) and so on. General idea of this design is: A stand-alone keypad for time adjustment, six digital tube display dynamic scan method. AT89C52 which is the core component, while the use of digital tube LED dynamic display "time", "sub", "seconds." Compared with the traditional mechanical watch, clock timer with walking precise, intuitive display, and so on. Its time period is 24 hours, was full scale is "23:59:59", another time with school functions and so on. The system also has the hardware design is simple, high stability, low cost and so on.

The design of the concrete realization of the function of major hardware and software from the start of two parts. Hardware components: modular design of hardware circuits, and clock circuit for the microcontroller interface, and the work of the entire hardware circuits to provide a unified operating frequency; reset circuit to ensure the system can have a fixed initial state; LED display circuit directly in the visual shows the effect achieved by software and hardware circuits, with a line drive 74LS244 as AT89C52 used for power-driven output transistor 9012 to provide a total of Yang LED digital tube series scan drive voltage; buzzer circuit in the system's operation is hearing The clear tips; button on the clock timer circuit to switch between the various functions; power supply circuit provides operating voltage is not fixed, and each part of the design circuit are given. Software part: According to the design function of the design process, including the main program and the display routines; for the time time the timer T0 interrupt service routine; used to indicate time to adjust cell count of the number of flashes or stopwatch timer T1 interrupt service routine , transfer function of process time, stopwatch function procedures, alarm time setting function procedures and other routines.



Keywords: AT89C52 LED display 74LS244









目 录



摘 要 i

Abstract ii

第一章 绪 论 1

第二章 设计方案的确定 2

第三章 系统硬件电路的设计 4

第一节 控制电路的设计 5

一、主芯片选定 5

二、主芯片时钟电路的设计 12

三、复位电路的设计 13

第二节 显示电路设计 16

一、显示器的选择 16

二、LED显示结构与原理 16

三、数码管的驱动方式 17

四、驱动芯片选用 18

五、电源驱动输出器件 19

第三节 蜂鸣器电路的设计 20

第四节 按键电路设计 20

第五节 电源电路设计 21

第四章 控制系统的软件设计 23

第一节 主程序 23

第二节 显示子程序 23

第三节 定时器T0中断服务程序 24

第四节 定时器T1中断服务程序 25

第五节 调时功腀@绦� 26

第六节 秒表功腀@绦� 26

第七节 闹钟时间设定功腀@绦� 26

第五章 控制程序的编制和调试 27

第一节 硬件调试 27

第二节 软件调试 27

第三节 软硬件联调 27

第四节 性能分析 27

总结和展望 29

参考文献 30

附 录Ⅰ 时钟计时器的硬件电路图 31

附 录Ⅱ 单片机汇编源程序清单 32

外文资料 54

中文译文 61

致谢语 67