摘 要

如今，随着互联网在工业中的广泛使用，局域网的智能控制已经全面铺开。在目前大多数控制系统中，独立控制方法的使用已不能满足人们对工业设备控制的要求。

通信行业的大力发展，为了使通信设备能够正常运行，通常采用很多配备智能监控接口的很多设备，为了有效管理这些配套设备，有必要将这些设备整合到一个统一的监控平台中，实现集中远程监控和管理。

我们控制的设备只是整个系统的一部分。同时，它也需要将自己的参数和运行条件输出到外部世界。智能集成众多设备，确保整个系统正常运行。

本文还将介绍该协议转换器的工作原理，硬件设计和软件设计，并在文章的最后给出了问题的设计和相应的解决方案。

在这个设计中，USB接口设计将被添加。与USB相比较RS232的缺点是传输速度很慢。这些RS485的缺陷只能通过USB来弥补，但是USB传输距离的不足正是RS485的优势。然后将两者结合起来，形成一个可靠，快速，低成本的远距离数据采集系统。

关键词：单片机；通讯协议；串口；监控；协议转换器

ABSTRACT

Nowadays, with the wide use of Internet in industry, the intelligent control of LAN has been spread out. At present, in most control systems, the use of independent control methods can no longer meet the requirements of industrial equipment control.

The communications industry vigorously develop, in order to make the communication equipment can run normally, usually adopt many many devices equipped with intelligent monitoring interface, in order to effectively manage these form a complete set of equipment, it is necessary to integrate these devices into a unified platform for the monitoring, realize remote monitoring and centralized management.

The equipment we control is only part of the system. It also needs to export its own parameters and running conditions to the outside world. Intelligent integration of a large number of devices to ensure the system running normally.The working principle, hardware design and software design of the protocol converter are also introduced in this paper.

In this design, the USB interface design will be added. The disadvantage of RS232 compared with USB is that the transmission speed is very slow. These defects of RS485 can only be made up by USB, but the lack of USB transmission distance is the advantage of RS485. The two are then combined to form a reliable, fast and low-cost remote data acquisition system

Key Words：SCM；Communication protocol；Serial port；Monitoring Protocol

目 录

1 概述.............................................................1

1.1课题的意义..................................................1

1.2设计的任务和要求............................................1

2 系统实现原理及硬件设计...........................................2

2.1系统实现原理................................................2

2.1.1设计原理介绍............................................2

2.1.2通讯协议................................................2

2.1.3数据交换流程............................................3

2.2.系统硬件设计................................................3

2.2.1主要芯片介绍............................................3

2.2.2硬件设计原理............................................9

2.2.3硬件看门狗设计.........................................12

2.2.4抗外界干扰设计.........................................12

2.2.5USB接口连接设计........................................12

2.2.6复位专用芯片...........................................14

3 系统软件设计....................................................16

3.1数据采集方案设计...........................................16

3.2软件设计...................................................17

3.2.1主程序流程设计.........................................17

3.3数据帧传输设计.............................................19

4 系统调试与仿真..................................................25

5 总结与体会......................................................31

参考文献...........................................................32

附录I.............................................................33

附录II............................................................34