基于P87C591的CAN总线通信系统设计

论文介绍了基于P87C591单片机的CAN总线通信系统的设计。P87C591内嵌CAN控制器,在设计中只需要接上CAN总线收发器PCA82C250和TTL和RS232的电平转换器,就能构成通信系统的节点,简化了硬件设计,提高了可靠性。本文对硬件电路和软件设计进行详细的分析。     

CAN总线智能测控节点的设计

分析了P87C591这种Philips公司近期推出的内带CAN控制器的8位高性能的微处理器的结构,给出了CAN定时寄存器的设定,提出了以P87C591为主构成的CAN智能节点的硬件框图,并提供了CAN通信的初始化、发送、接收各部分的程序设计．     

基于CAN总线的云台镜头解码器设计

针对闭路电视监控系统中云台镜头解码器的通讯通常采用RS-485协议,而控制器局域网络(CAN)是一种能有效支持分布式控制和实时控制的串行通讯网络,具有高性能、高可靠性的特点.以P87C591单片机为控制器,设计基于CAN总线的解码器系统,并给出硬件电路和软件编程,开发了CAN应用层通讯协议,实现了控制数据的快捷传输.     

基于P87C591的CAN总线系统智能节点的设计

介绍了P87C591单片机和CAN总线的特点,并给出了基于P87C591单片机的智能CAN节点的硬件电路和软件结构.硬件设计中对需要注意的问题给出了详细的介绍,软件设计在自制定协议的基础上,重点介绍了初始化、接收处理子程序.     

I/O模块的DeviceNet接口设计

简要分析了DeviceNet面向对象的应用层协议技术，并用Philips公司的P87C591在片CAN控制器芯片实现了对DeviceNet应用层协议核心的编制，给出了硬件连接电路。     

基于单片机P87C591的多主机系统

在单片机组成的多机系统中，因P87C591具有CAN总线，从而可以构成非主从式的多主机系统，即系统中的每个单片机都可以是主机．在此基础上介绍了P87C591单片机的硬件电路、软件设计及错误处理机制．     

基于P87C591的CAN总线系统智能节点的设计

介绍了P87C591单片机和CAN总线的特点，并给出了基于P87C591单片机的智能CAN节点的硬件电路和软件结构，硬件设计中对需要注意的问题给出了详细的介绍，软件设计在自制定协议的基础上，重点介绍了初始化、接收处理子程序。     

基于DSP芯片的接触式自动找平控制器

针对摊铺机自动找平控制系统的功能和实际工程要求，分析了其液压系统和控制原理，给出了自动找平系统的控制方案。以TMS320LF2407A为控制核心。运用P87C591单片机为处理器的智能传感器节点，完成了接触式自动找平控制器设计。该控制器具有“控制窗口”、“停车待料”和“数据恢复”等功能，保证了系统的控制性能。采用软硬件相结合多重滤波和时间片轮换控制处理方法，有效解决了控制器易受外界环境干扰以及系统的超调问题。试验结果表明，该控制器性能稳定，抗干扰性强。     

采用SAE J1939的CAN/LIN总线汽车内部网设计

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。     

基于CAN总线无功功率补偿器的研究与设计

针对目前供变电系统的无功功率补偿器,提出一种基于CAN总线无功功率补偿器.无功功率补偿器CPU采用P80C591作为核心部件,通过外接的测量电路实现参数的采集和控制.并通过CAN总线通信接口可以实现与上位计算机的通信功能,完成供变电系统的信息化和自动化.     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that