It allows data to be read into the CPU and written from the CPU. 它允许数据读入CPU也支持从CPU读出来。
Each controller on a bus can be individually addressed by the CPU, this is why the software device driver can write to its registers and thus control it. 在总线上的每个控制器可以被CPU所单独寻址,这是软件设备驱动程序能写入寄存器并能控制这些控制器的原因。
Once the power of a computer is turned on, all the behaviors are under the control of CPU. 计算机一旦通电运行,则所有的行为都要在它的控制之下运行。