目 录

摘要··································································································2

关键字·······························································································2

系统分布图·······················································································2

一、流水灯·····················································································3

二、数码管·····················································································5

三、矩阵键盘·················································································7

四、蜂鸣器·······················································································9

五、时钟电路··················································································11

六、片外扩展··················································································12

七、LCD1602·················································································13

八、AD转换电压表······································································15

1

九、DA控制波形·········································································17

实验总结························································································19

附录1：系统总体布局·································································19

附录2：本系统所用源程序···························································19

摘要：本系统以

单片机最小系统实验报告

ATMEL 公司生产的AT89C51单片机为核心，包括软件设计

和硬件设计两大类。其中硬件设计包括两部分：一是系统配置，及按照系统要求配置外围电路，如键盘，数码管，流水灯，A/D转换和D/A转换等；二是系统扩展，即是单片机内部功能单元不能满足应系统用要求时，必须在片外给出相应的电路，如单片机的片外扩展。而系统中的应用软件是根据功能要求设计的，每个应用软件都应可靠地实现系统的各种功能。我们在设计电路时还充分地考虑了硬件电路的可扩展性和软件的可读性和可移植性。我们的系统基本完成并能够执行实验所要求的各项功能。

关键字：AT89C51、发光二极管、液晶显示器、数码管、矩阵键盘、74HC573、

片外RAM、OP07、ADC0809、DAC0832

系统分布图：

2

一、流水灯

1、实验原理及实验结果：发光二极管加正向电压时导通，加反向电压时截止。通过每次对P1口某个I/O口送入高电平使其发光，其余的I/O送低电平使其截止，每次送电平时调用延时0.2s。通过不断调整高电平的位置，最后达到流水效果 。

2、实验原理图：

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P1.0P1.1P1.2P1.3P1.4P1.5P1.6R1470R2470R3470R4470R5470R6470R7470P1.7R8470流水灯D1LEDOUT+5VD2LEDD3LEDD4LEDD5LEDD6LEDD7LEDD8LED 3、实验流程图：

5V 4