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1.
提出了一种在Windows下响应硬件中断的实时串行通讯的模式,针对不同编程语言的特点,用BorlandC++编制程序对口直接操作,并响应执行硬件中继程序接收数据,利用DDE将数据传送用Delphi编制的程序进行管理。  相似文献   

2.
针对实时操作系统中要求中断响应实时性强的特点,提出了将中断响应分为中断处理和中断服务两部分,并且根据这种中断响应机制设计了多级中断服务请求队列,对临界资源的保护进行了探讨。这些技术应用于某型号高空无线电高度表,使其测高值达到15000m,误差为低空1%。  相似文献   

3.
在S波段测波雷达系统中,系统的相干性直接影响了系统对海浪参数的测量。对于采用数字信号处理器(digital signal processor,DSP)为核心处理器的微波雷达系统,由于DSP的SYSBIOS系统对硬件中断的响应和任务调度存在时间不定性,破坏了系统的相干性,导致回波信噪比下降。针对这一问题,提出利用DSP的可编程实时单元子系统(programmable real-time unit subsystem,PRUSS)对中断采集信号进行实时查询与响应,可以实现中断的无延迟响应,严格保证了雷达对信号回波采集的相干性。  相似文献   

4.
介绍了Win9x的内核结构及硬件中断,并讨论了虚拟设备驱动程序VxD的编程方法.使用VtoolsD类库,编写了基于ISA总线数据采集卡的驱动程序VxD,实现了硬件中断的处理例程,解决了在Windows下利用中断采集数据的问题.  相似文献   

5.
虚拟仪器是1种以计算机为工具,以各种新型软件为平台的新型电子测试仪器.为了开发友好界面,系统操作平台普遍采用Windows9x系统.但该操作系统不能由用户直接控制硬件,需要开发专门的硬件设备驱动程序,即通过一系列的虚拟设备驱动程序来管理硬件,如进行中断响应、I/O端口读写或直接存储器存取(DMA).为此,研究了Windows9x平台的虚拟环境、虚拟设备驱动程序VxD的基本方法,比较了在Windos9x中实现硬件中断的2种方法,结合开发工具VtoolsD得出了用C++语言编写的硬件中断的具体编程实例.通过该仪器的开发,成功地解决了数据采集的实时性和安全性问题.  相似文献   

6.
MCS-51系统外部中断响应频率的测试与研究   总被引:1,自引:0,他引:1  
分别使用6MHz和12MHz晶振频率,测试MCS-51系统的外部中断响应频率。实验结果表明:由于中断服务时间和中断响应延迟的存在,MCS-51系统的外部中断响应频率是受到限制的;最高可测试的外部中断响应频率大约是65kHz。本实验为合理和有效应用MCS-51系统的中断控制资源提供了可靠的实验数据。  相似文献   

7.
应用中断控制技术模拟3种不同的中断响应延迟,定量测定分析MCS-51 中断响应延迟中对断控制的影响,结果表明:MCS-51系统内置计使用低分系数对高率计数脉冲计数时,受中断响应延迟的影响会产生较大的计数误差,同时发现长短不同的中断响应延迟对于内置计数器的有效分频系数的限制有所不同,文中还探讨了有效使用调整模型消除计数误差的方法。  相似文献   

8.
基于Win95/98实时控制系统快速响应中断的方法   总被引:1,自引:0,他引:1  
在计算机工业控制领域 ,越来越多的基于 DOS的实时控制系统和检测系统正在向 Windows上移植 ,实现对中断的快速响应是实时控制系统和检测系统最基本的要求。文章介绍在 windows95 /98环境下 ,采用工具 Vtools D在 C+ + 编程环境下编写 Vx D(虚拟设备驱动 )的一种简便有效的方法来实现对硬件中断的快速响应  相似文献   

9.
章研究了M*Core的中断机制,设计了与M*Core兼容的中断控制器,该控制器具有中断响应快及中断处理方案多样的优点;同时给出了实测的中断控制器的性能结果。  相似文献   

10.
Linux内核调度器的调度开销巨大,无法满足实时应用需求.为此设计并实现了基于多核Linux的用户态实时多任务调度框架ULight.ULight共包括三个核心模块:多任务调度模块、定时器模块以及用户态中断处理模块.多任务调度模块在Linux用户态提供基于优先级可抢占的实时多任务调度方案,旨在减少任务调度和切换开销;定时器模块则为多任务调度提供高精度的定时服务,以支持分时调度和任务休眠,并提供更多的抢占点;用户态中断处理模块通过在内核态和用户态之间构造中断处理的快速通道,使用户态任务可以直接处理硬件中断,保证中断处理的实时性和高效性.实验表明,ULight的任务切换效率明显优于Linux的线程切换效率;定时系统可以提供精度为20μs的稳定的定时服务;用户态中断处理模块能够在用户态完成对硬件中断的快速响应.  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.
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   

14.
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   

15.
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   

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.
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.  相似文献   

18.
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-  相似文献   

19.
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-  相似文献   

20.
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  相似文献   

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