基于CAN总线的多点温度监测和报警系统设计.doc

基于CAN总线的多点温度监测及报警系统设计 第 PAGE 5 页 共 NUMPAGES 52 页 基于CAN总线的多点温度监测及报警系统设计 摘要 本文设计的是一套基于CAN总线的多点温度检测及报警系统，主要是对粮仓的温度监控，以确保储粮的安全。 系统设计分为主控模块和监控模块。主控监控两模块的微处理器都采用AT89S52单片机。为了实现主控模块对监控模块的实时监测，在主控端和监控端处都设计有CAN通信电路，由控制器SJA1000和收发器82C250组成CAN通信接口。另外，主控端的外围电路部分包括时钟电路功能模块、EEPROM存储电路模块、串口通信电路模块、译码电路功能模块、液晶显示屏模块；监控端的外围电路部分为温度传感器。主控端的时钟芯片选用DS12887，EEPROM存储芯片选用户AT24C16，显示屏采用FM12232B液晶模块。监控端的温度传感器采用数字传感器DS18B20，系统设置温度传感器的阐值为50℃。 本文给出了系统的结构和软硬件设计方案，可实现实时温度测量、越限报警等功能。该系统具有可靠性好、通信速率高、抗干扰能力强等特点。本系统还适用于在粮仓、北方暖气和热水供应中心、大面积水泥铺建等多种场合。 关键词：CAN总线；DS18B20；AT89S52  Based on CAN ABSTRACT This paper designs a multi-point temperature detection and alarm system based on CAN bus , this system is mainly used to monitor the temperature of granary, to ensure the safety of the stored grain. This system is divided into the main control module and the surveillance module. The microprocessor of the main control module and the surveillance module both use DSP AT89S52 microcontroller. In order to achieve real-time monitoring and measuring of the surveillance module,CAN communications circuits are designed at the port of the main control module and the surveillance module,which is composed by the controller SJA1000 and the 82C250 communications interface. In addition, the external circuit section of the main control module includes the clock circuit modules, EEPROM memory circuit module, serial communication circuit module, decoding circuit modules, LCD modules; the main portion of the external circuit section of the surveillance module is the temperature sensor. The clock chip of the main control module uses DS12887, the EEPROM memory chip can select AT24C16, the LCD display module can select FM12232B. The temperature sensor of the surveillance module use the digital sensor DS18B20, the lininal value of the temperature sensor is setted at 50 ℃ by the system. This paper presents the architecture of the system and the hardware and software design proposal , enabling the func