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1.
微机系统数据采集接口实验研究   总被引:1,自引:0,他引:1  
介绍了基于微机系统的数据采集实验卡的结构和软硬件设计.该数据采集卡基于ISA总线设计,具有中断和查询两种采样工作模式,能完成多通道模拟信号输入采样和数模转换输出实验,程序对可编程计数器控制,能完成不同采样速率的实验.学生通过该实验可加深对系统总线、模/数、数/模转换、可编程计数器等硬件的理解和运用,增强编写底层驱动程序的能力.  相似文献   

2.
本文通过对MCS-51系列单片机硬件结构的研究,提出并实现了一种简单可行的多I/O口扩展原理。在充分考虑了单片机的总线结构的前提下,利用总线设计技术,采用线选法,最大可扩展八位并行I/O口42个;同时,使ROM的空间任意浮动,便于软件开发与调试。利用这一原理设计的多I/O口系统,芯片少,硬件简单,成本低廉,运行可靠,可广泛应用于多组数据采集及多目标控制等场合。  相似文献   

3.
本文设计的挖掘机控制系统采用CAN总线网络结构,主控制器和远程I/O以ARM7微控制器LPC2000为核心,负责开关信号输入、模拟信号输入、数字信号输入和驱动等功能的处理,软件部分包含数据采集、数据通信和数据处理三大部分。  相似文献   

4.
付云峰  蒋学程  高贵鹏 《应用科技》2005,32(2):40-42,45
简单介绍了I2C总线,讨论了在TMS320C6711上扩展I2C总线的方案,并比较采用多通道缓冲串口(McBSP)和采用可编程逻辑器件这两种实现I2C总线接口协议的方法.从硬件连接和软件编程的方便性考虑,利用多通道缓冲串口(McBSP),用软件编程来模拟I2C总线协议,从而实现I2C总线接口的方法更简单,硬件设计更容易.并以TMS320C6711初始化视频解码芯片(SAA7111)为例,给出了相应的硬件电路以及模拟I2C总线协议的软件实现.  相似文献   

5.
通过引进消化吸收开发的方式,研建了AGRSS航测系统。ADASNT系统控制及数据采集软件是其配套开发的航测软件。在WindowsXP操作环境下,以C++Builder为开发工具,很好地解决了系统访问硬件的一些关键技术,实现了计算机与外设之间的串口通信、CPU访问I/O端口,以及模拟信号的输出等,并实现了基于WindowsXP平台的航空物探数据的采集、记录、显示等有关功能。  相似文献   

6.
用DSP主机端口实现虚拟I2C总线主控器   总被引:4,自引:2,他引:2  
针对TMS320C54x系列DSP(Digital Signal Processor)的I/O资源缺乏问题,通过配置主机接口(HPI:Host Port Interface)或多通道缓冲串行口(McBSP:Multichannel Buffered Serial Port)作为通用I/O引脚,模拟I2C总线的时钟线SCL(Serial Clock)和数据线SDA(Serial Data);采用软件模块实现虚拟外设等方法,完成了I2C总线主控器功能.给出了以该系列DSP作为I2C总线的主控器与I2C总线从控器的无缝连接方法.结合视频应用实例,叙述了由TMS320VC5409配置具有I2C总线接口的视频处理器SAA7111A的具体过程.结果表明,利用DSP的HPI接口实现片上虚拟I2C总线主控器,是可行的、经济的.  相似文献   

7.
FPGA与I2C总线器件接口设计   总被引:3,自引:0,他引:3  
本文介绍了现场可编程门阵列FPGA与I2C总线器件接口的设计方法.其特点是用VHDL语言编程,利用FPGA的普通I/O口模拟产生I2C总线规程的接口信号时序,实现PFGA与I2C总线器件的数据通信.本文给出了PFGA与I2C总线存储器件24CO1/02连接的硬件和软件设计的应用实例.  相似文献   

8.
储成君 《科学技术与工程》2013,13(19):5692-5695,5701
针对航天测试中被测模拟信号种类多、数量大的应用背景,设计了一种基于FPGA的多通道数据采集系统。系统采用了模块化的设计,各模块通过内部的三通连接器实现层叠式互联,减小了硬件复杂度并提高了系统的通用性和灵活性。分析采集电路中运放输出异常现象,并给出了解决方案,提高采样精度,并提出了一种多路模拟开关并联运行的采样控制方法,利用FPGA内部的块RAM资源,建立模拟信号通道采样的查找表结构,通过对采样通道地址及模拟开关使能信号进行编码和存储,实现了大量的不同类型的模拟信号的实时采样。  相似文献   

9.
本文针对VXI总线自动测试系统中常用的数字I/O模块展开研究.分析了数字I/O模块的关键技术,提出了相应的技术解决途径,给出了系统硬件和软件设计方案;阐明了整个数字I/O模块的工作流程以及各部分电路所完成的功能,着重介绍了模块与VXI总线的接口部分设计、数据输出时的数据发生功能和数据输入时的数据采集功能的设计.  相似文献   

10.
采用浮点放大器和CPLD设计了多通道数据采集系统.其浮点放大器根据输入信号范围,放大适当的倍数,保证了数据采集系统的动态测量范围;CPLD具有丰富的内部资源和大量I/O管脚,处理速度快,可实现灵活多变的控制流程;双端口RAM作为A/D转换与CPU之间的桥梁,为高速数据吞吐提供了有力的硬件支持;结合以上几方面的优势,系统总体上实现了高速、高精度数据采集.  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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