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PCI9054工作模式???!!!
各位大侠:
小弟现在想开发一块PCI9054采集卡,但是对9054德工作模式不是很熟悉,想请问大侠几个问题: 1)用DeviceIoControl向局部总线上的I/O控制口写数据,是否需要设置9054为slave方式?为什么? 2)如果用Direct Slave Operation,9054是否需要设定DEVICE_DESCRIPTION?是否还需要用DMA Adapter申请缓存? 3)如果9054用Direct Master Opteration,是否也需要设定DEVICE_DESCRIPTION?如何申请缓存? 谢谢谢谢!!!!!!! |
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沙发#
发布于:2004-08-04 14:55
1)用DeviceIoControl向局部总线上的I/O控制口写数据,是否需要设置9054为slave方式?为什么?
2)如果用Direct Slave Operation,9054是否需要设定DEVICE_DESCRIPTION?是否还需要用DMA Adapter申请缓存? 3)如果9054用Direct Master Opteration,是否也需要设定DEVICE_DESCRIPTION?如何申请缓存? 回答: 1: 设为adapter salve mode, because it is simple for software designer 2:DMA 用demand mode, Because it is most efficent 3:Direct Master Opteration would use DEVICE_DESCRIPTION. it is on your demand for buffer cache |
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