【正文】 基于 CAN總線的多點(diǎn)溫度監(jiān)測(cè)及報(bào)警系統(tǒng)設(shè)計(jì) 第 1 頁 共 52 頁 基于 CAN 總線的多點(diǎn)溫度監(jiān)測(cè)及報(bào)警系統(tǒng)設(shè)計(jì) 摘要 本文 設(shè)計(jì)的是一套 基于 CAN 總線的多點(diǎn)溫度檢測(cè)及報(bào)警系統(tǒng) ，主要是對(duì)糧倉(cāng)的溫度監(jiān)控，以確保儲(chǔ)糧的安全 。 系統(tǒng)設(shè)計(jì)分為主控模塊和監(jiān)控模塊。主控監(jiān)控兩模塊的微處理器都采用 AT89S52單片機(jī)。為了實(shí)現(xiàn)主控模塊對(duì)監(jiān)控模塊的實(shí)時(shí)監(jiān)測(cè)，在主控端和監(jiān)控端處都設(shè)計(jì)有 CAN通信電路，由控制器 SJA1000 和收發(fā)器 82C250 組成 CAN 通信接口。另外，主控端的外圍電路部分包括時(shí)鐘電路功能模塊、 EEPROM 存儲(chǔ)電路模塊、串口通信電路模塊、譯碼電路功能模塊、液晶顯示屏模塊；監(jiān)控 端的外圍電路部分為溫度傳感器。主控端的時(shí)鐘芯片選用 DS12887， EEPROM 存儲(chǔ)芯片選用戶 AT24C16，顯示屏采用 FM12232B液晶模塊。監(jiān)控端的溫度傳感器采用數(shù)字傳感器 DS18B20， 系統(tǒng)設(shè)置溫度傳感器的闡值為 50℃ 。 本文給出了系統(tǒng)的結(jié)構(gòu)和軟硬件設(shè)計(jì)方案，可實(shí)現(xiàn)實(shí)時(shí)溫度測(cè)量、越限報(bào)警等功能。該系統(tǒng)具有可靠性好、通信速率高、抗干擾能力強(qiáng)等特點(diǎn)。 本系統(tǒng)還適用于 在 糧倉(cāng) 、 北方暖氣和熱水供應(yīng)中心 、 大面積水泥鋪建等多種場(chǎng)合 。 關(guān)鍵詞 ： CAN 總線； DS18B20； AT89S52 基于 CAN總線的多點(diǎn)溫度監(jiān)測(cè)及報(bào)警系統(tǒng)設(shè)計(jì) 第 2 頁 共 52 頁 BASED ON CAN BUS MULTIPOINT TEMPERATURE MONITORING AND ALARMING SYSTEM DESIGN ABSTRACT This paper designs a multipoint 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 realtime monitoring and measuring of the surveillance module,CAN munications circuits are designed at the port of the main control module and the surveillance module,which is posed by the controller SJA1000 and the 82C250 munications interface. In addition, the external circuit section of the main control module includes the clock circuit modules, EEPROM memory circuit module, serial munication 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 function of realtime temperature measurement and the offlimited alarm .The system has good reliability, high transmission rate, strong antiinterference and so on. This system can also be applied to the granary, the north central heating and hot water supply center, the cement paving of a large area and other occasions. Keywords: CANbus； DS18B20； AT89S52 基于 CAN總線的多點(diǎn)溫度監(jiān)測(cè)及報(bào)警系統(tǒng)設(shè)計(jì) 第 3 頁 共 52 頁 目 錄 1 緒論 ................................................................... 5 背景介紹 .......................................................... 5 國(guó)內(nèi)外相關(guān)技術(shù)發(fā)展概況 ............................................ 5 溫度傳感器的發(fā)展概況 ........................................ 5 現(xiàn)場(chǎng)總線概況 ................................................ 6 溫度監(jiān)測(cè)及報(bào)警系統(tǒng)的應(yīng)用前景 ..................................... 7 2 現(xiàn)場(chǎng)總線 CAN 原理介紹 ................................................... 7 現(xiàn)場(chǎng)總線簡(jiǎn)介 ...................................................... 7 CAN 總線簡(jiǎn)介 ...................................................... 8 CANbus 的產(chǎn)生與發(fā)展 ......................................... 8 CANbus 的基本工作原理 ....................................... 9 CANbus 的特征 .............................................. 10 CAN 協(xié)議簡(jiǎn)介 ................................................ 11 3 基于 CAN 多點(diǎn)溫度檢測(cè)系統(tǒng)的總體設(shè)計(jì) .................................... 15 系統(tǒng)總體方案設(shè)計(jì) ................................................. 15 系統(tǒng)設(shè)計(jì)的主要器件選擇 ........................................... 16 微處理器 ................................................... 16 SJA1000 控制器 .............................................. 17 PCA82C250 總線收發(fā)器 ........................................ 19 溫度傳感器的選擇 ........................................... 20 顯示器的選擇 ............................................... 24 系統(tǒng)硬件結(jié)構(gòu)組成 ................................................. 25 4 系統(tǒng)的硬件設(shè)計(jì) ........................................................ 27 單片機(jī)最小系統(tǒng)設(shè)計(jì) ............................................... 27 串口電路設(shè)計(jì) ..................................................... 28 EEPROM ........................................................... 29 基于 CAN總線的多點(diǎn)溫度監(jiān)測(cè)及報(bào)警系統(tǒng)設(shè)計(jì) 第 4 頁 共 52 頁 CAN 通信電路設(shè)計(jì) ................................................. 29 CAN 通信結(jié)構(gòu)框圖 ............................................ 30 CAN 通信電路電源模塊 ........................................ 31 CAN 通信接口電路 ............................................ 31 時(shí)鐘電路設(shè)計(jì) ..................................................... 32 譯碼電路 ......................................................... 33 液晶顯示屏 ....................................................... 34 溫度傳感器 ....................................................... 35 鍵盤電路 ......................................................... 36 報(bào)警電路 ........................................................ 37 5 系統(tǒng)的軟件設(shè)計(jì) ........................................................ 38 系統(tǒng)整體軟件設(shè)計(jì) ................................................. 38 主控模塊軟件設(shè)計(jì) ................................................. 38 CAN 控制器的初始化 .......................................... 38 主控端巡檢監(jiān)控端 ........................................... 41 外圍電路軟件設(shè)計(jì) ........................................... 41 監(jiān)控模塊軟件設(shè)計(jì) ................................................. 47 CAN 通信模塊軟件設(shè)計(jì) ........................................ 48 溫度傳感器的軟件設(shè)計(jì) ....................................... 48 6 結(jié)論 .................................................................. 49 參考文獻(xiàn) ................................................................ 50 致謝 .................................................................... 50 附錄 ..........................