【正文】 統(tǒng)能夠滿足絕大多數(shù)客戶的要求?？扇?xì)怏w探測器瓦斯?jié)舛葯z測和過程,然后反應(yīng)CAN/ 485轉(zhuǎn)換器的需求來傳輸數(shù)據(jù)基于RS485 到CAN/ 485轉(zhuǎn)換器。分離技術(shù)的可燃?xì)怏w報警器是相當(dāng)成熟,但它仍然不能滿足系統(tǒng)的要求,具有多個節(jié)點和廣泛的報道。硬件和軟件設(shè)計的主要控制器和/ 485轉(zhuǎn)換器是在描述細(xì)節(jié)。最后，一些重點是特別強(qiáng)調(diào)設(shè)計?，F(xiàn)在大多數(shù)Bustype可燃?xì)怏w報警系統(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。根據(jù)CAN總線，將CAN/ 485轉(zhuǎn)換器整理數(shù)據(jù),并傳送到主控制器,。 氣體檢測傳感器檢測氣體濃度，并切換到0V5V的電壓信號。在系統(tǒng)設(shè)計中，主控制器是最重要和最困難的部分。 氣體報警SYSTEM硬件設(shè)計主控制器主控電路主要包括兩部分：電源電路，微控制器和各種I / O模塊。實時數(shù)據(jù)量和歷史數(shù)據(jù)量是非常大的，所以FM24C256(32 K E2PROM)和SD2200EPI(時鐘芯片以32 KB SDRAM)通過TWI總線擴(kuò)展。這也是雙方驗收濾波和信息管理能力。點，線，圓，長方形，格子和其他復(fù)雜的圖形可以很容易地通過簡單的指令被設(shè)計出來。 LM246是用來給三個報警信號。其特點表現(xiàn)如下：1）達(dá)到或超過TIA/EIA485A標(biāo)準(zhǔn)的要求。多主機(jī)通信的方法可用于CAN總線上，但仍估計故障和保持平衡每個節(jié)點的主機(jī)使用主控制器。注冊TXBnEID8商店發(fā)件人的ID和TXBnEID0商店氣體報警或聯(lián)動模塊的地址。每個數(shù)據(jù)幀之間必須有適當(dāng)?shù)难舆t，如果有人能注意不斷地發(fā)送消息，或其他溢出錯誤是易發(fā)生。 MCP2515。s very suitable to used in CAN/485 converter. Converter mainly used to convert data format between CAN and RS485. The circuit mainly includes CAN part and RS485 CAN part is similar to the part in the main controller showed in . The RS485 bus part is showed. LowPower and high performanceprice ratio chip SN65HVD3082 is used as the RS485 transceiver. Its features show as follow:1） Meets or exceeds the requirements of the TIA/EIA?485A standard.2） Low quiescent power: mA active mode and 1 nA shutdown mode.3） 1/8 unit load—up to 256 nodes on a bus. In order to enhance system stability, 6N137 is used 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 node sets corresponding shielding and acceptance bits. Such a method can distinguish 127 CAN nodes and fully meet the requirements. Register TXBnEID8 stores sender39。 converter。1) Prop Seg + Phase Seg 1 = Phase Seg 22) Prop Seg + Phase Seg 1 = TDELAY 3) Phase Seg 2 Sync Jump Width 以關(guān)閉揚(yáng)聲器，不僅VCC引腳，但也必須改變低水平的OSC1和OSC2引腳，否則一些LM246不能正常工作。2. CAN/485轉(zhuǎn)換器的軟件設(shè)計 接收信號變換器主控制器由基于CAN總線的中斷。鍵值檢測和處理部分的主要功能是檢測天氣推觸摸屏，然后回應(yīng)。3）1/