基于单片机的电子秒表.doc

课程设计(论文)说明书 题 目： 基于单片机的电子秒表 院 （系）： 信息与通信学院 专 业： 电子信息工程 学生姓名： 　　　　　 学 号： 指导教师： 职 称：  摘 要 近年来随着科技的飞速发展，单片机的应用正在不断地走向深入。 本设计采用AT89S52单片机、3-8线译码器74LS138 关键字： 单片机; 数字电子秒表; LED数码管 Abstract In recent years along with the rapid development of science and technology, SCM applications are constantly deepening. In this paper based on singlechip digital electronic stopwatch design. This design is mainly characterized by the use of 6 digital tube display, in seconds, while the precision is not very high, but solves the stopwatch is cumbersome, and the design is also provided with a reset and pause button, convenient for users to control. The design of the digital electronic stopwatch system using AT89S52 microcontroller as the center device, using the timer / counter timing and counting principles, combined with the display circuit, the LED digital tube as well as the external interrupt circuit to design the timer. The software and hardware combination, so that the system can achieve 6 LED display, display the time from seconds to hours, a relatively wide range of timing. The software system adopts C language programming input program. The hardware also used 3-8 line decoder 74LS138 chip, 74hc573 latch and an MAX232 chip. Key word: SCM; Digital electronic stopwatch; LED Digital tube 目 录 引言.................................................1 1 电子秒表的工作原理.....................................1 1.1 电子秒表简介.............................................1 1.2 电子秒表的工作原理.......................................1 2 硬件设计................................................2 2.1 键盘模块.................................................2 2.2 控制模块.................................................3 2.3 显示模块...............................................