8237 DMA本身有16位地址线，每个通道一次可传输64KB，如定义64KB为1页，并在8237与主机连接的控制电路中增加12位页地址寄存器，其寄存器的12位页地址作为它的高12位地址，此时8237能寻址的内存容量为(63)。

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NET is both a business strategy from Microsoft and its(71)of(72)support for what are known as Web services, the ability to use the Web rather than your own computer for various services. Microsoft's goal is to provide individual and business users with a(73)interoperable and Web-enabled interface for applications and computing devices and to make computing activities increasingly Web browser-oriented. The .NET(74)includes servers; building-block services, such as Web-based data storage; and device software. It also includes Passport, Microsoft's fill-in-the-form-only-once identity(75)service.

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操作系统是一种系统软件，它有许多种类，PC-DOS是一种(12)操作系统， Windows是具有图形界面的(13)运行方式的操作系统。(14)是在体系结构上采用了客户机服务器模式的网络操作系统。

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