排序方式: 共有28条查询结果,搜索用时 93 毫秒
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介绍了在Windows系统下用Visualc++、DDK和DriverStudio软件对PCI(peripheral component interconnect)设备驱动程序的编写。阐述了PCI设备驱动程序的分层结构和编写方式。PCI驱动属于内核模式驱动程序中的即插即用驱动,PCI的即插即用功能是本丈重点介绍对象。另外介绍了PCI设备驱动通过配置空间获取设备资源的过程与方法,以及驱动程序与操作系统之间的通讯机制。 相似文献
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基于嵌入式Linux数据采集系统的设计 总被引:1,自引:0,他引:1
介绍了使用ARM芯片LPC2138进行数据采集系统设计的方法,其中包括Linux操作系统下基于ARM芯片LPC2138的UART串口驱动程序的开发,利用串口与GPRS模块相连实现无线上网的方法。由于系统体积小,性能好且价格较为经济,在大规模气象监测网络体系中将发挥积极的作用。 相似文献
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作者在本文中介绍了基于PC和Windows 9X平台下用中断方式实现数据采集的方法;并对虚拟设备驱动程序(VxD)和VtoolsD工具箱进行了简要介绍,通过对源代码的分析,说明了实时硬件中断VxD的实现过程。 相似文献
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基于CPLD的线阵CCD驱动时序电路设计 总被引:3,自引:1,他引:2
CCD驱动时序电路的设计是CCD应用的最基本也是最关键的问题.通过复杂可编程逻辑器件(CPLD)搭建时序电路,可以充分发挥其"可编程"技术特性,简化电路结构并具备极强的通用性.介绍利用CPLD实现驱动电路的主要特性、工作原理和设计思想并利用VHDL语言实现了驱动程序,并给出具体的仿真结果. 相似文献
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Human-driven topographic effects on the distribution of forest in a flat,lowland agricul-tural region简 总被引:1,自引:0,他引:1
Mette V. ODGAARD Peder K. B CHER Tommy DALGAARD Jesper E. MOESLUND Jens-Christian SVENNING 《地理学报(英文版)》2014,24(1):76-92
Complex topography buffers forests against deforestation in mountainous regions. However, it is unknown if terrain also shapes forest distribution in lowlands where human impacts are likely to be less constrained by terrain. In such regions, if important at all, to- pographic effects will depend on cultural-historical factors and thus be human-driven (an- thropogenic) rather than natural, except in regions where the general climate or extreme soils limit the occurrence of forests. We used spatial regression modeling to assess the extent to which topographic factors explain forest distribution (presence-absence at a 48x48 m resolu- tion) in a lowland agricultural region (Denmark, 43,075 km2) at regional and landscape scales (whole study area and 10x10 km grid cells, respectively), how landscape-scale for- est-topography relationships vary geographically, and which potential drivers (topographic heterogeneity, forest cover, clay content, coastal/inland location) determine this geographic heterogeneity. Given a moist temperate climate and non-extreme soils all landscapes in Denmark would naturally be largely forest covered, and any topographic relationships will be totally or primarily human-driven. At regional scale, topographic predictors explained only 5% of the distribution of forest. In contrast, the explanatory power of topography varied from 0%-61% at landscape scale, with clear geographic patterning. Explanatory power of topog- raphy at landscape scale was moderately dependent on the potential drivers, with topog- raphic control being strongest in areas with high topographic heterogeneity and little forest cover. However, these conditioning effects were themselves geographically variable. Our findings show that topography by shaping human land-use can affect forest distribution even in flat, lowland regions, but especially via localized, geographically variable effects. 相似文献