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第五节 3+ Ethernet编程技术要领网络研究人员总是非常关心如何在已有系统软件的基础上开发新软件以扩展网络的功能,使网络适用于更广泛的领域,这就涉及到网络的编程技术。下面,我们先讲述3~+Ethernet编程技术要领。一、网络板的端口地址前面提到过,对于主机来讲,网络板就如同一个外部设备驱动板,主机通过输入/输出指令或者DMA方式和网络板交换数据、控制信息和状态信息。无疑,对于编程来讲,了解各端口及它们的作用是最重要的。网络板上共有十六个寄存器。对应于十六个输入/输出端口。下表列出了各寄存器的对应端口号以及读写操作时的功能:
Section 5 3 + Ethernet programming techniques Network researchers are always very concerned about how to develop new software based on the existing system software to expand the network function, make the network suitable for a wider area, which involves the network programming technology. Below, we first talk about 3 ~ + Ethernet programming techniques. First, the network board port address As mentioned earlier, for the host, the network board is like an external device driver board, the host through the input / output instructions or DMA mode and network board to exchange data, control information and status information. Undoubtedly, for programming, it is paramount to understand the ports and their role. There are sixteen registers on the board. Corresponds to sixteen input / output ports. The following table lists the corresponding port numbers for each register and the functions for reading and writing: