单片机系统中标志位的应用

Application of Bit-flags in Single-chip Microcomputer System

简要介绍了MCS-51系列单片机中的位寻址区和位操作指令。位寻址区和位操作指令构成了MCS-51系列单片机独具的布尔处理机。布尔处理机实际上是一个完整的一位微计算机,在开关决策、逻辑电路仿真和实时控制方面非常有效。位寻址区和位操作指令的一个最重要的应用就是用于设置标志位。这一特点使得单片机系统在开关决策、逻辑电路仿真、智能检测和实时控制方面的到了非常广泛的应用。通过一个实例给出了利用标志位来判断按键是否被按下的算法。

The bit operation instruments and bit addressable locations in MCS-51 series microcontroller are introduced. Bit addressable locations and bit operation instruments compose the boolean processor of MCS-51 series microcontroller. The boolean processor is an integrated 1- bit-micro computer. An important use of them is set bit-flags, and this characterisitic makes single-chip microcomputer system a wide apphcation in switch-decision making, logical circuit simulation, intelligent detection and real-time control. An algorithm of using bit-flags is presened to detect if a key is pressed or not with an actual example.