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1.
通用USB芯片价格低,功能全,但是基于其进行手机U盘功能开发,需要芯片驱动、协议处理和文件管理等固件支持。本工作通过在手机固件中增加USB芯片驱动、USB通信、Mass Storage协议和Fat文件系统的固件代码,在一款国产手机上实现了基于通用USB接口芯片的U盘功能。其设计思路对于开发其他USB设备有一定参考价值。  相似文献   

2.
张淼  赵冒童 《福建电脑》2014,(12):122-125
随着USB键盘的出现,迫切需要设计出一种实时性高、成本低的USB键盘。结合当前USB接口的技术,设计了一种基于STM32F103RBT6芯片并运行一套Coo Cox Co OS英蓓特嵌入式实时操作系统的USB键盘。首先在芯片的引脚上,设计了USB接口的硬件电路。然后利用芯片自带的USB库,设计了矩阵式键盘扫描和数据传输的软件流程。通过测试,结果表明该键盘实时性较高。  相似文献   

3.
PDIUSBD12芯片能够实现微控制器的并行总线到USB总线的接口功能,使用PDIUSBD12芯片可以实现多种类型的USB外设。本文介绍了使用该芯片实现现场数据经红外传输的USB数据采集系统。  相似文献   

4.
针对实现嵌入式USB主机互联的需求,提出了以PDIUSBD 12为USB控制芯片的USB On—The—Go(USB OTG)设备解决方案。通过分析芯片驱动、控制单元数据交换程序设计,建立PC—PC USB接口连接器,为USB主机间提供对等功能的USB设备接口,通过统一的数据缓冲区,实现了两台USB主机不借助于USB集线器的互联方案。  相似文献   

5.
USB接口的高速数据采集卡的设计与实现   总被引:15,自引:0,他引:15  
讨论了基于USB接口的高速数据采集卡的实现。该系统采用TI公司的TUSB3210芯片作为USB通信及主控芯片,完全符合USB1.1协议,是一种新型的数据采集卡。  相似文献   

6.
文方  王武  王民慧  陈进军 《测控技术》2002,21(Z1):35-37,39
介绍了利用USB总线技术进行数据采集系统的设计方案,并以PIC16C712芯片为控制器,USBN9603为USB总线接口芯片,完成了光栅位移传感器USB数据接口的设计和实现.  相似文献   

7.
TMS320C54xx DSP的USB接口实现   总被引:3,自引:0,他引:3  
介绍了DSP芯片上USB接口的实现。使用USB接口芯片AN2131Q实现DSP和PC机之间的通信,在AN2131Q和TMS320VC54XXDSP之间加有FIFO芯片,可提高数据的传输速度,使最大数据传输速度超过USB总线的速度。  相似文献   

8.
一款集成HUB的USB设备控制器的设计   总被引:1,自引:0,他引:1  
介绍了USB设备控制器的基本功能和原理,提出了一款基于6502MCU的通用的带HUB的全速USB设备控制器的体系结构,并完成了整个芯片的设计,而且通过了FPGA验证。这款芯片可以用来开发带HUB的全速USB设备、全速USB设备或全速USBHUB。  相似文献   

9.
在视频数字解码系统中,需要将AD采样后形成的数字视频流传送到计算机,以便进行模拟解码等算法设计;文章提供了一种FPGA视频信号采集系统数字视频流传输方案,利用FPGA芯片提供的IP核和内嵌的PowerPC 405硬核以及USB2.0芯片CY7C67300实现了数字视频流的USB传输方式;文章介绍了USB芯片的固件开发,针对于系统的特定应用对USB接口的功能进行了定制,建立起PowerPC 405与USB控制器之间的数据通道,将存储在DDR SDRAM中的数字视频流传给USB控制器,并最终通过USB接口传输给PC机;实现了数字视频流的USB传输。  相似文献   

10.
基于PDIUSBD12的S3C44B0X下USB通信的实现   总被引:1,自引:0,他引:1  
本文基于ARM7内核S3C44B0X微处理器和USB接口芯片PDIUSBD12,详细设计了S3C44B0X与芯片PDIUSBD12的连接方法,并给出了Device设备中USB固件程序,Host端USB驱动程序和应用程序的设计方案,实现了上下位机的USB通信。  相似文献   

11.
The new method of defuzzification of output parameters from the base of fuzzy rules for a Mamdani fuzzy controller is given in the paper. The peculiarity of the method is the usage of the universal equation for the area computation of the geometric shapes. During the realization of fuzzy inference linguistic terms, the structure changes from the triangular into a trapezoidal shape. That is why the universal equation is used. The method is limited and can be used only for the triangular and trapezoidal membership functions. Gaussian functions can also be used while modifying the proposed method. Traditional defuzzification models such as Middle of Maxima − MoM, First of Maxima − FoM, Last of Maxima − LoM, First of Suppport − FoS, Last of Support − LoS, Middle of Support − MoS, Center of Sums − CoS, Model of Height − MoH have a number of systematic errors: curse of dimensionality, partition of unity condition and absence of additivity. The above-mentioned methods can be seen as Center of Gravity − CoG, which has the same errors. These errors lead to the fact that accuracy of fuzzy systems decreases, because during the training root mean square error increases. One of the reasons that provokes the errors is that some of the activated fuzzy rules are excluded from the fuzzy inference. It is also possible to increase the accuracy of the fuzzy system through properties of continuity. The proposed method guarantees fulfilling of the property of continuity, as the intersection point of the adjustment linguistic terms equals 0.5 when a parametrized membership function is used. The causes of errors and a way to delete them are reviewed in the paper. The proposed method excludes errors which are inherent to the traditional and non- traditional models of defuzzification. Comparative analysis of the proposed method of defuzzification with traditional and non-traditional models shows its effectiveness.  相似文献   

12.
A method of synthesis of fuzzy stabilization systems for a broad class of dynamic objects under the assumption that the mathematical model of the object is not known a priori is proposed. The control is formulated in the form of a proportional law of adjustment as a function of a macro-variable; the square of the Euclidean norm of the phase variables is adopted as the macro-variable. An analogous variable characterizes the distance of the object from the equilibrium position. Despite the simplicity of the control law, its sign remains constant due to the fact that the macro-variable is positive-definite over the entire phase space. The switching times of the signals are determined by fuzzy identification of the system’s dynamic modes on the basis of measurement of the derivatives of the macro-variable.  相似文献   

13.
目前大多数研究对复杂社会网络关键节点影响力的识别都是静态的,缺乏动态变化的分析。采用可拓聚类方法对动态变化下的科教人际网络进行量化分析,首先以多属性决策法计算每个节点重要性,再利用变异系数权重法计算得该节点综合重要性量值,之后划分等级并取标准正域和正域区间,利用可拓关联函数计算每个节点与每个等级的关联度,关联度值最大的等级即为该节点对应等级,最后分析同一社会网络节点在不同时间点的重要性等级变化。可拓聚类方法尝试从动态上对网络节点重要性进行把握,最后通过实例验证了该方法的有效性。  相似文献   

14.
Measurements of spring phenological dates in boreal regions using NDVI can be affected by snowmelt. This impacts the analysis of interannual variations in phenology and the estimates of annual carbon fluxes. For these two objectives, snowmelt effect must be removed from the phenological detection. We propose a methodology for determining the date of onset of greening in the 1982-2004 period using SPOT-VEGETATION (VGT) and NOAA Advanced Very High Resolution Radiometer (AVHRR) data. From 1998 onwards, the date of onset of greening is taken as the date at which the Normalized Difference Water Index (NDWI), calculated from SPOT-VGT near and short-wave infrared bands, starts increasing. This index decreases with snowmelt but increases with vegetation greening. For the 1982-2001 period, the date of onset of greening is the date at which AVHRR-NDVI equals a pixel specific threshold (PST), determined using the results of the NDWI method in the years common to the two datasets. The methods are validated using in situ measurements of the dates of leaf appearance. RMSE of 6.7 and 7.8 days, respectively, is found using NDWI-VGT and PST-NOAA methodologies, and the difference between the two methodologies in the common years is small. Very importantly, the dates are not biased. The interannual variations of the 23-year spring phenology dataset on the study area in northern Eurasia are analysed. In average over the study area, an advance of 8 days and a delay of 3.6 days are, respectively, found over the periods 1982-1991 and 1993-2004. These results confirm and complete previous studies about the greening trend, remove the uncertainty due to snow, and may improve carbon budget calculations.  相似文献   

15.
The laser is a joining tool which is particularly suitable for the application in microtechnology. The process variant laser transmission joining can be used both for welding thermoplastics and bonding of silicon and glass. The investigations presented in this paper cover detailed examinations of both processes. Concerning laser transmission welding of plastics it is examined how far the content of carbon black in the material influences the formation of the weld seam. It is shown that the optical depth of penetration, the weld seam width as well as the formation of the weld morphology differ with varying content of carbon black. Selective laser radiation bonding (SLB) is a novel method for joining silicon and glass based on the transmission heating of the interface of both joining partners and the thermo-chemical principles of silicon direct bonding. SLB shows advantages in reference to the thermal load of sensitive components like sensors and to the selectivity of the joining geometry. In this study the principle method of SLB and the latest advances like the integration of the thermal process control in the laser processing head will be presented. Also experimental test results of the process with constant laser power and thermal process control and the comparison of them will be shown.An erratum to this article can be found at  相似文献   

16.
多数社交网络影响力最大化算法的研究只关注于所选种子节点集合的影响力是否最优,忽略网络自身传播影响力的固有能力。本文对网络进行渗流模拟,计算渗流后网络的主连通分量随着传播概率改变的趋势,并且求得主连通分量大小增加开始变快的相变点,从而计算网络自身传播影响力的固有能力。通过相变值与种子节点集合大小的换算,求得当前网络最佳的种子节点集合大小。将种子节点集合大小限制在最佳大小范围内即可获得最佳的影响力。在kareteclub、football、highschool和socdolphins社交网络数据集上进行实验,验证了该方法的有效性。  相似文献   

17.
概念的形成是实现人工智能的基础,为研究人工智能系统中概念的形成过程,从人对事物形成概念的过程出发进行了研究。比较人和人工智能系统的概念形成过程得到了如下特点:人的优势在于能自主地确定对象表象和对象功能中的各种特征和划分等,能在对象、描述性定义和功能性定义对应关系不完备情况下通过思维和联想建立概念;人工智能系统的优势在于丰富的对象表象感知能力,对象的各种特征和划分的长期存储、运算和分析能力;而人工智能的概念形成过程存在的缺点基本与人的概念形成过程的优点对应。因此本文认为人工智能的概念形成过程必须关注因素的智能识别、功能的系统实践和人经验知识的有师学习。现有技术在缺乏人经验知识的情况下,人工智能系统不能自主建立概念和知识库,不能实现智能过程。  相似文献   

18.
归纳总结了计算机用户在日常工作、生活中可能碰到的多种代表性的电脑软硬件故障和问题及解决方法。各种故障问题类型和故障排除思维习惯来编排,具体包括开关机故障、死机故障、显示故障、声音故障、存储设备故障、CPU故障、内存故障、主板故障。在碰到电脑故障时,能快速判断和解决一些有规律可循的常见故障,以及如何维护电脑、如何避免电脑故障。  相似文献   

19.
李程程  王晓云 《软件》2013,(12):186-189
针对目前流行的OpenFlow技术,本文提出OpenFlow的标准进展、商业价值和连通性测试。该方法根据控制层面和转发层面相分离的技术,采用移动研究院内网拓扑进行测试。实验结果表明,通过在BigSwitch controler上进行相关命令配置就可实现二层的OpenFlow交换机互联的不同网段主机的通信。OpenFlow是SDN技术中一种关键的接口协议,SDN是对网络的抽象, OpenFlow是对单个转发面设备的抽象。OpenFlow交换机和Control er的出现为新型互联网(NGN)体系结构的研究提供了实验途径。  相似文献   

20.
毛华  武秀 《智能系统学报》2020,15(3):514-519
三支概念构建是三支形式概念分析的研究内容之一。为丰富三支概念的研究内容,利用矩阵结构,提出一种三支概念构建算法。首先,给出属性矩阵的定义,并设计利用属性矩阵构建属性三支概念的算法过程,对实例进行算法运算,以此对算法步骤进行说明,对算法正确性进行了相应验证。其次,定义对象矩阵,并设计依据此矩阵构建对象三支概念的算法,对实例进行算法运算。经上述研究验证,所提算法正确且有效。研究结果为三支概念在数据处理中的应用提供了更多选择。  相似文献   

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