SCM应用系统中时钟管理方法的研究

为在单片机 (SCM)应用系统中精确实现时钟管理 ,在分析研究了该应用系统中实现时钟管理原理的同时 ,列举了 3种实现时钟管理的方法 ,并通过比较说明了这些方法的应用特点。结果表明 :(1)通用型定时器 /计数器 (T/C)方法简便易行 ,但只适用于各任务间执行时间不重叠的情形 ;(2 )专门时钟管理接口芯片 (如MC146 818A)实现时钟管理 ,可极大地减少CPU被中断的次数 ,提高系统的实时性 ;(3)实时多任务操作系统实现时钟管理 ,可同时进行多个任务的调度 ,实现多任务的并列运行

STUDY ON METHODS OF CLOCK MANAGEMENT IN SCM APPLICATION SYSTEM

It is very important for the SCM application system to realize clock administration accurately.For this purpose , three methods of realizing clock administration has been listed while its principle was analyzed and studied,and the application characteristics of these methods have also been explained by comparison . Results show that : (1)the general timer/ counter(T/C)method is simple and convenient,but only suitable for the situation that the executive time among all the assignments is not overlap ;(2)to realize clock administration by special connection chips (such as MC146818A) can greatly reduce the amount of the CPU being interrupted and raise the time characteristic ;(3)to realize clock administration by the operation system of inactual time can adjust several assignments in the same time and realize the side by side operation of multi-assignment.