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1.
在低速电子通信网络中LIN总线协议的应用分析   总被引:1,自引:0,他引:1  
范建英 《科技资讯》2012,(22):21-21
LIN是一种串行通讯网络,交换数据的形式有多种,LIN总线总是起辅助的作用,在没有CAN总线的地方,使用LIN总线的成本较低,本文基于LIN技术的定义,对在低速电子通信网络中LIN总线协议的应用进行了初步解析。  相似文献   

2.
采用SAE J1939的CAN/LIN总线汽车内部网设计   总被引:1,自引:0,他引:1  
以国产汽车为应用对象,设计以CAN总线为主、LIN总线为辅,并以当前应用最广泛的SAE J1959协议为主干协议的汽车内部通信网络,将汽车动力系统和车身控制系统的通信网络分成高速CAN网络、低速CAN网络和LIN网络三部分。选取Philips公司的P87C591等器件,设计了CAN、LIN总线节点、主控制器节点和相应的连接节点。此设计方案具有成本低、可扩展性高等特点,可作为适用于华晨、奇瑞、吉利等国产汽车内部网设计。  相似文献   

3.
以国产汽车为应用对象,设计以CAN总线为主、LIN总线为辅,并以当前应用最广泛的SAE J1939协议为主干协议的汽车内部通信网络,将汽车动力系统和车身控制系统的通信网络分成高速CAN网络、低速CAN网络和LIN网络三部分。选取Philips公司的P87C59等器件,设计了CAN、LIN总线节点、主控制器节点和相应的连接节点。此设计方案具有成本低、可扩展性高等特点,可作为适用于华晨、奇瑞、吉利等国产汽车内部网设计。  相似文献   

4.
汽车上的电控系统数量越来越多,为了提高电控单元之间互相通信性能和降低导线成本,提出了一种基于CAN/LIN总线的车载通信网络,将CAN总线网络应用在高速的驱动系统,LIN总线网络应用在低速的车身车灯控制系统,两者通过网关进行数据交换.仿真测试表明,本车载通信网络的设计合理,通信可靠,能够实现CAN/LIN总线网络之间的数据传输.  相似文献   

5.
结合现有汽车电子技术及汽车网络技术的发展概况,提出了一种基于Freescale8位单片机M68HC908EY16的LIN总线汽车灯光控制系统解决方案.简要介绍了LIN通讯协议,结合本芯片较为详细的介绍了LIN总线技术在灯控模块中的应用.完成了灯控系统协议的制定,并给出了系统硬件原理图以及软件设计流程.  相似文献   

6.
针对控制系统中单片机和上位机的通信问题,制定了一个适用于微型控制系统的网络通信协议.给出了协议制定的原则,分析了通信协议中校验部分存在的问题,定义了一种适合微型控制系统的校验码-非0校验,阐述了该协议在单片机控制系统中实现的过程,验证了该协议的有效性及稳定性。  相似文献   

7.
CAN总线协议实现方法研究   总被引:1,自引:0,他引:1  
在CAN总线通信网络的建设中,CAN总线控制器实现了CAN总线协议的大部分内容.首先介绍了CAN总线的概况,简单介绍了CAN总协议的内容,详细介绍了有限状态自动机的组成特点以及利用有限状态自动机实现CAN总线协议的方法.最后根据有限状态自动机的设计要求,详细介绍了CAN节点的各种状态以及各个状态之间的转换关系.  相似文献   

8.
传统的汽车车窗多采用机械式的控制方法,存在着不易操作、布线复杂、电磁干扰严重等问题.随着汽车电子化的不断提高,控制节点的不断增多,传统线束的单对单连接方式已经无法满足人们的需要.汽车总线技术因其独特优势,能够很好的解决连线增加所带来的问题,因此采用总线技术成为汽车发展的必然趋势.由于汽车车窗工作频率较低,因此对数据传输的速率要求较低.若采用CAN总线通讯成本较高,而LIN总线作为一种辅助的总线网络,仅使用一根线就能够实现数据的通讯,因此使用LIN总线可大大节省成本.本文设计了一种基于LIN总线的汽车车窗控制系统,实现了对汽车车窗的总线控制,为实际应用提供了一种可行的解决方案.  相似文献   

9.
刘茜 《科技信息》2010,(7):94-96
LIN(Local Interconnect Network)总线是面向低端分布式控制的一类多路复用通信协议。本文主要对该协议进行了较为详细的描述,并给出了LIN在车身控制中的应用。  相似文献   

10.
基于LIN总线车灯控制系统的研制   总被引:3,自引:0,他引:3  
于Local Interconnect Network(LIN)汽车总线技术, 在DP-51H单片机数据通信综合仿真实验仪上提供一个实现LIN-bus通讯网络软硬件调试/ 仿真的环境, 综合考虑汽车在特殊环境下的工作性能, 研制了基于LIN协议的汽车车灯控制 系统. 该系统根据LIN协议开发设计了智能化主节点和从节点, 完成了主从节点的硬件选型 和电路设计以及软件分析和程序实现. 在车灯系统的设计中, 节点间的LIN通讯完全符合LIN 1.2规范协议, 该协议基于通用的UART/SCI硬件接口, 采用ISO9141单线传输标准, 采取单 主多从的总线型拓扑结构并提供方便的用户应用编程接口.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

18.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

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