计算机控制技术课程设计说明书
双机串口通信系统的设计
学生姓名： 周全 学号： 1227034252 学 院： 中北大学朔州校区 专 业： 电气工程及其自动化 指导教师： 冯娜
2016年 1 月
目 录
1 绪论 ·············································································································· 1 1.1 课题简介 ····································································································· 1 1.2 设计目的 ································· 1 1.3 设计任务 ····································································································· 1 1.4 设计方法 ····································································································· 1 2 设计内容与所用器件 ······················································································ 3 2.1 基本功能 ····································································································· 3 2.2 可选器件 ····································································································· 3 3 方案论证与比较 ····························································································· 4 3.1 汇编语言和C语言的特点及选择 ·································································· 4 3.2 同步通信和异步通信的比较 ········································································· 4 3.3 并行通信与串行通信的比较 ········································································· 4 3.4 串行通信程序设计的比较 ············································································· 5 4 硬件系统设计 ································································································· 6 4.1 52单片机串行通信功能 ··············································································· 6 4.2 MAX232芯片 ································································································· 8 4.3 整体电路设计 ······························································································ 9 5 软件设计 ······································································································ 10 5.1 串行通信软件实现 ····················································································· 10 5.2 程序流程图 ······························································································· 11 6 系统调试与存在的问题 ················································································· 13 6.1 硬件调试 ··································································································· 14 6.2 软件调试 ··································································································· 15 总 结 ·············································································································· 16 附 录 ·············································································································· 17 附 录B ：源程序 ···························································································· 18 参考文献 ········································································································· 22
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1 绪论
1.1 课题简介
当今社会，随着人们物质生活的不断提高，电子产品已经走进了家家户户，无论是生活或学习，还是娱乐和消遣几乎样样都离不开电子产品，大型复杂的计算能力是人脑所不能胜任的，而且比较容易出错。计算器作为一种快速通用的计算工具方便了用户的使用。计算器可谓是我们最亲密的电子伙伴之一。本设计着重在于分析计算器软件和开发过程中的环节和步骤，并从实践经验出发对计算器设计做了详细的分析和研究。
单片机由于其微小的体积和极低的成本，广泛的应用于家用电器、工业控制等领域中。在工业生产中。单片微型计算机是微型计算机的一个重要分支，也是颇具生命力的机种。单片微型计算机简称单片机，特别适用于控制领域，故又称为微控制器。
本系统就是充分利用了8952芯片的I/O引脚。系统以采用MCS-52系列单片机Intel8052为中心器件来设计基于52单片机的双机串行通信设计。 1.2 设计目的
通过本次课题设计，应用《计算机控制技术》、《单片机原理及其接口技术》等所学相关知识及查阅资料，完成简易双机串行通信设计，以达到理论与实践更好的结合、进一步提高综合运用所学知识和设计的能力的目的。
通过本次设计的训练，可以使我在基本思路和基本方法上对基于MCS-52单片机的嵌入式系统设计有一个比较感性的认识，并具备一定程度的设计能力。 1.3 设计任务
实现两片单片机之间的串行通信，A机将0xff发送给B机，在B机的数码管上静态显示，B机将0~f动态循环发送到A机，并在其数码管上显示。 1.4 设计方法
本次设计，对于两片89C52，采用RS232进行双机通信。发送方的数据由串行口TXD段输出，经过电平转换芯片MAX232将TTL电平转换为RS232电平输出，经过传输线将信号传送到接收端。接收方也使用MAX232芯片进行电平转换后，信号到达接收方串行口的接收端。接受方接收后，在数码管上显示接收的信息。为提高
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抗干扰能力，还可以在输入输出端加光耦合进行光电隔离。
软件部分，通过通信协议进行发送接收，主机先送AAH给从机，当从机接收到AAH后，向主机回答BBH。主机收到BBH后就把数码表TAB[16]中的10个数据送给从机，并发送检验和。从机收到16个数据并计算接收到数据的检验和，与主机发送来的检验和进行比较，若检验和相同则发送00H给主机；否则发送FFH给主机，重新接受。从机收到16个正确数据后送到一个数码管显示。
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2 设计内容与所用器件
2.1基本功能
利用AT89C52完成两片单片机的进行串行通信。 2.2可选器件
52系列单片机、电容、7段LED数码管、MAX232（即下图1中各器件）
图1.系统电路图
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