首先研究CAN總線和SAE J1939協(xié)議，提出一種基于MC9S12HZ256微控制器的總線式汽車數(shù)字儀表解決方案。詳細(xì)介紹SAE J1939協(xié)議的報(bào)文幀格式及應(yīng)用層協(xié)議中發(fā)動(dòng)機(jī)相關(guān)參數(shù)的定義，以及步進(jìn)電機(jī)及其驅(qū)動(dòng)和車速信號(hào)的處理方法。該數(shù)字儀表系統(tǒng)硬件平臺(tái)由微處理器和信號(hào)采集和信息處理及顯示等模塊組成。軟件設(shè)計(jì)部分編程實(shí)現(xiàn)了對(duì)CAN總線和各傳感器數(shù)據(jù)的讀取、處理。該系統(tǒng)能夠?qū)崟r(shí)反映車輛工況。
Abstract:
In this paper，CAN bus and SAE J1939protocol are researched，and a vehicle digital instrument solution based on MC9S12HZ256MCU is proposed.The message frame format and some engine-related parameters’definition in SAE J1939application layer protocol are introduced in detail.Stepper motor and its driver，the methods of speed signal process-ing are also introduced.The hardware platform of vehicle digital instrument is composed by MCU，signal acquisition mod-ule，and signal processing and displaying module.Data receiving and processing from CAN bus and sensors are accom-plished by programming，and vehicle condition can be reflected in real-time.
闡述了一個(gè)由上位PC機(jī)和AT89C52下位單片機(jī)組成的主從分布式溫度巡回檢測(cè)系統(tǒng)。主從機(jī)采用RS-485 串行通訊標(biāo)準(zhǔn)進(jìn)行通信，可在下位單片機(jī)實(shí)現(xiàn)基本的溫度數(shù)據(jù)巡回檢測(cè)基礎(chǔ)上，由上位PC機(jī)實(shí)現(xiàn)綜合處理功能或擴(kuò)展為遠(yuǎn)程操作。整個(gè)系統(tǒng)具有巡檢速度快，擴(kuò)展性好的特點(diǎn)。
Abstract:
In this paper,a top PC and AT89C52 under-bit microcontrollers from the main component of the tour distributed temperature detection system is presented. Master and slave can use RS-485 serial communication standards for communications.Based on next-bit machine for basic goods temperature detected data Tour, the top can achieve the integrated treatment of PC functions or for the expansion of long-distance operation. The entire inspection system is fast, expansion.
介紹了CAN總線和P87C591單片機(jī)的特點(diǎn)，給出了基于P87C591單片機(jī)的信號(hào)采集節(jié)點(diǎn)的軟、硬件設(shè)計(jì)，指出了硬件電路設(shè)計(jì)中應(yīng)注意的問題，在軟件設(shè)計(jì)中重點(diǎn)介紹了節(jié)點(diǎn)初始化、報(bào)文發(fā)送和報(bào)文接收等子程序。
Abstract:
The features of CAN Bus and the microcontroller P87C591 are introduced, and the design of hardware circuit and soft configuration of the signals collection node based on P87C591 are presented. The problems in designing hardware circuit are discussed.Initialization subprogram, transmiting subprogram and receiving subprogram are emphasized in soft configuration.
針對(duì)船舶氣象儀保障維修而設(shè)計(jì)的船舶氣象儀測(cè)試系統(tǒng)，包括信息處理終端、主儀器檢測(cè)模塊、傳感器檢測(cè)模塊，各個(gè)模塊都采用基于AVR單片機(jī)的嵌入式系統(tǒng)，模塊之間通過CAN總線進(jìn)行通信。結(jié)果表明，船舶氣象儀測(cè)試系統(tǒng)能夠快速檢測(cè)船舶氣象儀故障，與單純依靠人工方式排查故障相比，故障檢測(cè)時(shí)間縮短了60%以上。
Abstract:
The test system of ship meteorological instrument was developed to satisfy the maintenance of ship meteorological instruments，which composed of information processing terminal， testing module of main instrument and testing module of sensors. Each of these modules included an embedded system based on microcontroller of AVR series and communicated with other module by CAN bus. The results show that the test system can judge the fault of ship meteorological instrument quickly and shorten the fault detection time as much as 60% compared with simple manual troubleshooting.
SAE J1939協(xié)議是由汽車工程協(xié)會(huì)(SAE)定義的，SAE J1939協(xié)議在商用車輛、艦船、軌道機(jī)車、農(nóng)業(yè)機(jī)械和大型發(fā)動(dòng)機(jī)中是應(yīng)用最廣泛的應(yīng)用層協(xié)議，基于傳輸可靠性能優(yōu)越的CAN-bus總線，可達(dá)到250Kbps的通訊速率。在協(xié)議中，不僅指定了傳輸類型、報(bào)文結(jié)構(gòu)及其分段、流量檢查等，而且報(bào)文內(nèi)容本身也做了精確的定義，SAE J1939協(xié)議由美國SAE( Society of Automotive Engineer)組織維護(hù)和推廣
