外文翻譯--一種新的可燃?xì)怏w報(bào)警系統(tǒng)的設(shè)計(jì)與實(shí)現(xiàn)-資料下載頁
2025-05-12 08:20本頁面
【導(dǎo)讀】結(jié)合總線RS485和總線CAN系統(tǒng)的設(shè)計(jì)與實(shí)現(xiàn)。主要介紹mcp2515的特點(diǎn)。硬件和軟件設(shè)計(jì)的主要控制器和/485轉(zhuǎn)換器是在描述細(xì)節(jié)。最后，一些重點(diǎn)是特別強(qiáng)調(diào)設(shè)計(jì)。目前,石油化工企業(yè)、百貨、住宅等,均要求對(duì)可燃?xì)怏w濃度檢測。國家相關(guān)標(biāo)準(zhǔn)日趨嚴(yán)格。雖然有許多可燃?xì)怏w報(bào)警系統(tǒng)在市場上,他們中的大多數(shù)都有非常高的錯(cuò)誤信息和低性能?，F(xiàn)在大多數(shù)Bus-type可燃?xì)怏w報(bào)警系統(tǒng)是基于RS485這并不是很穩(wěn)定,不能容納更多的探測器節(jié)點(diǎn)。在本文中,這一計(jì)劃是主控制器+CAN/485轉(zhuǎn)換器+燃?xì)馓綔y器。節(jié)點(diǎn)能力達(dá)數(shù)千。到現(xiàn)在為止在中國尚未報(bào)道氣體報(bào)警系統(tǒng)，根據(jù)這項(xiàng)計(jì)劃，它是連接的重要發(fā)展方向，具有廣闊的市場空間和發(fā)展前景。根據(jù)不同的核心價(jià)值也回應(yīng)并實(shí)施相應(yīng)觸摸屏功能。探測器將數(shù)據(jù)傳輸?shù)较鄳?yīng)的CAN/485轉(zhuǎn)換器基于RS485總線。微控制器和其它芯片進(jìn)入主循環(huán)程序運(yùn)行之前，必須初始化和啟動(dòng)界面顯示1分鐘。
【正文】 to separate circuit and magnetic beads and lightning protection devices are added to the circuit.IV. SOFTWARE DESIGN Design of the Main Controller Program flow of the main controller is described. Before running into the main loop program, the microcontroller and other chips must be initialized and the startup interface displays for 1 minute. In this process the system detects power state, key value and reads parameters. The system parameters mainly include using condition of nodes, password and other information. Multihost munication method may be used on CAN bus, but the main controller is still used as host for estimating faults and maintaining balance of each node. The system can work stably and quickly as soon as proper error handling method is taken. The main function of key value detection and processing part is to detect weather the touch screen is pushed and then respond it. Touchscreen images mainly include three pulldown menus: displaying menu, setting menu and control menu. Each menu has several pulldown options and all the functions are pleted by key value handling function. Interruption INT0 is used to receive data from CAN bus and 29 bits extended frame format is used to send and receive messages. Register TXBnSIDH is used as node39。s ID, and receiver39。s node sets corresponding shielding and acceptance bits. Such a method can distinguish 127 CAN nodes and fully meet the requirements. Register TXBnEID8 stores sender39。s ID and TXBnEID0 stores address of gas alarm or linkage module. So a set of data of gas alarm or linkage module can transmit by one frame data.2. Software Design of CAN/485 Converter Converter receives mands from the main controller by interruption based on CAN bus. Then it analyzes mands and executes different subfunction. Converter polls child nodes of this RS485 bus when it doesn39。t receive mands from the main controller. is program flow chart of CAN/485 converter.V. SEVERAL POINTS FOR ATTENTION IN THE DESIGN The program of CAN munication interruption and UART receiving interruption must be short enough. Otherwise, the munication efficiency will be influenced. There must be proper delay between each frame of data if some CAN note send message continuously, or else overflow error is easy to happen. Some requirements for programming of the time segments must be satisfied in order to avoid munication failure.1) Prop Seg + Phase Seg 1 = Phase Seg 22) Prop Seg + Phase Seg 1 = TDELAY3) Phase Seg 2 Sync Jump Width In order to close speaker, not only the VCC pin, but also the OSC1 and OSC2 pins must be changed to low level, otherwise some LM246 couldn’t work normally. To avoid disturbance of touch screen, the key values must be taken 3 groups at least.VI. CONCLUSION The bustible gas alarm system has high stability, nodes capabilities and its interface is friendly. PC can be added to the system via CAN adapter to realize displaying, setting and other functions. Now the product is going into mass production.
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