基于CAN总线的温度监测系统

摘要

控制器局部网(CAN—C0NTROLLER AREA NET的RK)是BOSCH公司为现代汽车应用领先推出的一种多主机局部网，由于其卓越性能现已广泛应用于工业自动化、多种控制设备、交通工具、医疗仪器以及建筑、环境控制等众多部门。其总线规范已成为国际标准，被公认为几种最有前途的总线之一。本文综述了CAN总线产生和发过程，概括了CAN总线优于其它现场总线的特点，结合生产中温度监控的实际需求，提出了将CAN总线应用于生产实践的设想。给出了基于CAN总线的温度监控系统的设计方案，设计了一种基于CAN总线的智能楼宇温度测控系统。以STC89C52RD单片机为核心，利用CAN总线技术和数字温度传感器DS18B20，组建了智能楼宇温度测控系统的节点及网络架构，给出了系统总体结构和关键的软件流程。测试结果表明，房间温度控制能满足设计要求，具有结构简洁、节能、实时性好及可靠性高等优点。

关键词：现场总线，温度传感器，节点，网络架构

I

A CAN network based temperature monitoring

system

ABSTRACT

Controller area network (CAN-C0NTROLLER AREA NET's RK) is a BOSCH company is the leading modern automotive applications, launched a multi-host the local network, because of its superior performance has been widely used in industrial automation, variety of control equipment, transport, medical equipment and construction, environmental control and many other sectors. The bus specification has become the international standard, recognized as some of the most promising of the bus. This paper reviews the production and development process of CAN bus, CAN bus, summarizes the characteristics superior to other field bus, temperature monitoring with the production of the actual demand, put forward a CAN bus used in the production practice of the idea. CAN bus is presented based on temperature monitoring system design, design of a CAN bus based temperature measurement and control system of intelligent buildings. The STC89C52RD microcontroller as the core, the use of CAN bus technology and the digital temperature sensor DS18B20, set up a temperature measurement and control system intelligent building node and network architecture, gives the overall system architecture and key software processes. The results show that the room temperature control to meet the design requirements, with a simple structure, energy, real good, and reliability.

Keywords: field bus, temperature sensors, nodes, network architecture

II

目录

摘要 ................................................................................................................. I ABSTRACT ....................................................................................................... II 第1章绪论.. (1)

第2章现场总线CAN原理概述 (2)

2.1 CAN总线产生和发展 (3)

2.2 CAN总线的概述 (4)

2.3 CAN总线的特点 (4)

2.4 CAN总线组织的基本规则 (6)

第3章温度监控系统的总体设计方案 (8)

3.1 系统要求 (8)

3.1.1 系统功能要求 (8)

3.2 系统总体设计方案 (8)

3.3 关键器件的选择 (9)

3.3.1 SJA1000芯片简介 (10)

3.3.1.1 SJA1000芯片特性 (10)

3.3.1.2 SJA1000内部结构 (10)

3.3.2 AT89C52单片机简介 (12)

3.3.3 CAN总线收发器82C250芯片简介 (13)

3.3.4 6N137光电耦合器 (14)

第4章系统的硬件设计 (16)

4.1 CAN通信电路设计 (16)

4.2 智能温度节点设计 (18)

4.3 外围电路硬件设计 (19)

4.3.1 数字温度传感器DS18B20 (19)

4.3.1.1 DS18B20的特点 (19)

4.3.1.2 DS18B20使用注意事项 (20)

第5章系统的软件设计 (21)

5.1 系统的软件设计 (21)

5.2 上位机的软件设计 (21)

5.2.1 CAN信息的接收 (22)

III