在读取方面使用中间内核缓冲区，可以允许内核缓冲区在应用程序不需要内核缓冲区内的全部数据时，充当 “预读高速缓存（readahead cache）” 的角色。

Using the intermediate buffer on the read side allows the kernel buffer to act as a "readahead cache" when the application hasn't asked for as much data as the kernel buffer holds.

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在应用程序中开辟了两个缓冲区，交替与传输卡上先进先出存储器（FIFO）通信，实现了主机到外设之间高速无间断数据传输；

In the design of application software, two buffers A and B were used to communicate with the FIFO on the card alternately. Thus the high speed continuous data transmission was achieved.

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