微机原理与接口技术课程设计-数字式秒表

微机原理与接口技术课程设计

1 目录

目录 ······································································································ 1

摘要 ······································································································ 1

关键词 ··································································································· 1

第一章 引言 ························································································· 2

第二章 硬件系统设置 ··············································································· 3

2.1 硬件系统原理图 ··································································································· 3

2.2 芯片资料介绍 ······································································································ 4

2.2.1 8253芯片 ······································································································· 4

2.2.1.1 8253内部计数器的3个引脚 ································································································ 4

2.2.1.2 8253的工作方式 ···················································································································· 4

2.2.1.3 8253的编程 ···························································································································· 4

2.2.2 8255芯片 ······································································································· 5

2.2.2.1 连接外设的数据端口 ············································································································· 5

2.2.2.2 8255工作方式 ························································································································ 5

2.2.2.3 8255的编程 ···························································································································· 5

2.2.3 8259芯片 ······································································································· 6

2.2.3.1 8259的编程及操作方式 ········································································································ 6

2.2.4 74LS240芯片 ··································································································· 7

2.2.4.1 74ls240内部结构 ·················································································································· 7

2.2.4.2 芯片介绍 ································································································································· 7

2.2.5 75452芯片 ····································································································· 7

2.2.5.1 75452内部结构 ······················································································································ 7

2.2.5.2 芯片介绍 ································································································································· 8

2.3 线路连线 ············································································································ 8

2.3.1 实验连线 ····································································································································· 8

2.3.2 时钟脉冲的产生 ························································································································· 8

2.3.3 键盘的设置 ································································································································· 9

2.3.4 LED显示器的设置 ···················································································································· 10

第三章 软件系统设置 ·············································································· 12

3.1程序流程图 ········································································································ 12

3.1.1 主程序流程图 ··························································································································· 12

3.1.2 ‘0’ 处理流程图（开始计时） ··························································································· 13

3.1.3 ‘1’处理流程图（名次存储） ····························································································· 13

3.1.4 ‘2’ 处理流程图（显示成绩） ··························································································· 14

3.1.5 ‘3’处理流程图（比赛结束1） ······················································································· 15

3.1.6 ‘4’处理流程图（比赛结束2） ·························································································· 15 微机原理与接口技术课程设计

2 3.1.7 中断处理流程图 ······················································································································· 16