144 resultados para USB


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由于Linux良好的开放性和USB总线极佳的通用性 ,USB设备在Linux操作系统中得到了广泛的应用。文中首先介绍Linux驱动程序的架构 ,然后介绍USB设备 ,重点说明USB驱动程序的实现

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介绍了基于U SB接口技术和CPLD技术的智能型的CAM AC机箱控制器的设计,该控制器设计简单,开发周期短,运行高效可靠,支持短周期。

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介绍了基于以太网技术和USB接口技术的智能型的CAMAC机箱控制器的设计,该控制器支持网络接口和USB接口,能够方便快捷的构成高速数据获取系统,运行高效可靠,且支持CAMAC短周期。

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研制了一种基于通用串行总线(USB)接口的微型电化学分析仪(μECS)。仪器采用了20位数模转换器和24位模数转换器,输出电位分辨率达到10μV;输出电位范围为-5~+5V;电流测量范围为1nA~5mA。软件支持循环伏安法等各种常用电化学方法。对仪器主要参数进行了测试,其电流灵敏度小于50pA;输入阻抗大于1011Ω;电位误差小于1mV;电流测量误差小于1%。利用μECS进行了金电极上自组装单分子层(SAM)电化学特性的研究。

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USB是一种新型的计算机接口规范,它由于具有传输速度快、可靠性高、易于连接等优点而被广泛应用于目前的PC外围设备中。文章介绍了Philips公司的PDIUSBD12芯片和Atmel公司的ATmega128芯片在便携式心电监测仪上的应用,并给出了相应固件程序的编写方法。

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针对环境温湿度检测的需求,设计了一种点对多点的星型无线温湿度监控网络。以无线通信模块nRF401为基础,配合AT89C2051和数字温湿度传感器SHT11构建了从机,以P89C51RD2BN单片机和USB接口芯片PDIUSBD12构建了主机。对系统的硬件原理及温湿度采集方法进行了介绍,对无线通信协议及USB固件设计方法进行了较详细分析。经上位机软件测试,系统运行稳定,具有较好实用性,可应用于多种场合的无线温湿度监测。

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本文介绍了一种利用DSP处理DM642、CPLD及USB芯片等器件构造的带有USB接口的图像采集和处理系统。设计了USB通信接口的硬件电路,在DSP/BIOS架构上编写了USB的固件程序和主机端的设备驱动程序。该系统可用于香烟包装流水线上的条包检测等对生产速度要求较高的工业流程领域。

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本文论述了CAN总线系统中CAN适配卡的重要作用,在分析其他CAN适配卡实现方案优缺点的基础上提出了一种基于USB的新型CAN适配卡的实现方案,并详细的阐述了设计方法,给出了具体的软硬件实现方案。

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USB接口的设备使用方便,发展迅速,文章结合高速公路车道收费系统中的实际问题,详细介绍了设计一个USB接口通信卡的过程,包括电路设计、器件选择、固件设计、驱动程序及其应用程序设计。

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基于USB接口技术的设备使用方便,发展迅速,文章结合高速公路车道收费系统中所涉及到的数据传输实际问题。详细介绍了设计一个USB接口设备的过程,包括硬件设计、固件设计、驱动程序及其应用程序设计。

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本文以中国科学院沈阳自动化研究所自动化装备研究室的项目——路桥收费系统为背景。首先阐述了路桥收费系统的组成结构,重点讨论了传统的收费控制子系统的构成和功能。然后在深入分析原有系统不足的基础上,本文提出了采用CAN总线技术和USB接口技术来构建一种全新的收费控制子系统的方法。并对这种方法进行了深入的研究,设计并实现了组成系统所需的核心器件,构成了原型系统,对系统的可行性进行了验证。 CAN总线是目前在中小型测控系统中应用非常广泛的总线之一,它非常适用于收费控制子系统中。USB接口技术是近几年来兴起的新型接口技术,它为外围设备与计算机的连接提供了一种方便、快捷的方法。在我们的系统中以基于USB的新型CAN适配卡代替了以往普通的CAN适配卡,为控制计算机联入CAN网开拓了新思路。 本文详细地阐述了系统中核心器件RS232/CAN、CAN/USB协议转换卡的设计与实现及原型系统的构建和测试方法。主要内容分为系统硬件的设计与实现、系统软件的设计与实现和测试系统的设计与调试三部分。具体包括了核心器件的设计原理、电子元器件的选择、电路原理图的设计、PCB板的制作、硬件的焊接与调试及协议转换卡的固件设计、驱动程序设计、上位机测试程序设计。最后利用所设计的软硬件构建了原型系统并进行了测试。

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A human-computer interface (HCI) system designed for use by people with severe disabilities is presented. People that are severely paralyzed or afflicted with diseases such as ALS (Lou Gehrig's disease) or multiple sclerosis are unable to move or control any parts of their bodies except for their eyes. The system presented here detects the user's eye blinks and analyzes the pattern and duration of the blinks, using them to provide input to the computer in the form of a mouse click. After the automatic initialization of the system occurs from the processing of the user's involuntary eye blinks in the first few seconds of use, the eye is tracked in real time using correlation with an online template. If the user's depth changes significantly or rapid head movement occurs, the system is automatically reinitialized. There are no lighting requirements nor offline templates needed for the proper functioning of the system. The system works with inexpensive USB cameras and runs at a frame rate of 30 frames per second. Extensive experiments were conducted to determine both the system's accuracy in classifying voluntary and involuntary blinks, as well as the system's fitness in varying environment conditions, such as alternative camera placements and different lighting conditions. These experiments on eight test subjects yielded an overall detection accuracy of 95.3%.

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A compact ultra-wideband (UWB) printed slot antenna is described, suitable for integration with the printed circuit board (PCB) of a wireless, universal, serial-bus dongle. The design comprises of a near-rectangular slot fed by a coplanar waveguide (CPW) printed on a PCB of size 20 × 30 mm2. It has a large bandwidth covering the 3.1–10.6 GHz UWB band, with omnidirectional radiation patterns. Further, a notched band centered at 5.45 GHz wireless local area network bands is obtained within the wide bandwidth by inserting a narrow slot inside the tuning stub. Details of the antenna design are described, and the experimental results of the constructed prototype are presented. The time domain studies on the antenna shows a linear phase response throughout the band except at the notched frequency. The transient analysis of the antenna indicates very little pulse distortion confirming its suitability for high speed wireless connectivity.

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An ultra-wideband (UWB) printed slot antenna, suitable for integration with the printed circuit board (PCB) of a wireless universal serial-bus (WUSB) dongle is presented. The design comprises a near-rectangular slot fed by a coplanar waveguide printed on a PCB of width 20 mm. The proposed design has a large bandwidth covering the 3.1-10.6 GHz UWB band, unaffected by the ground length, and omnidirectional radiation patterns. A linear phase response throughout the band further confirms its suitability for high-speed wireless connectivity.