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PC机使用三个主要的时钟类型:CPU时钟、实时钟和计时器时钟。下面分别说明每个时钟的概念、用途及其与DOS和BIOS服务的关系。 CPU时钟:控制在计算机中央处理器中的各种操作何时产生,决定用户程序的执行速度。通常,CPU时钟以一固定的时间间隔产生信号,用以控制计算机的操作。以这些固定的时间间隔产生的频率称为时钟频率,如PC/XT机是4.77MHz,PC/AT机可选为6MHz/8MHz/12MHz,各类的286兼容机是10-
PC uses three main types of clock: CPU clock, real-time clock and timer clock. The following describes each clock concept, purpose and its relationship with the DOS and BIOS services. CPU clock: control in the computer when the central processor in a variety of operations generated, the decision of the user program execution speed. Normally, the CPU clock generates signals at regular intervals to control the operation of the computer. The frequencies generated at these fixed time intervals are called the clock frequency, such as PC / XT machine is 4.77MHz, PC / AT machine optional 6MHz / 8MHz / 12MHz, various types of 286 compatible machine is 10-