在i.MX51芯片上降低系统功耗的一种方法  

A Power Consumption Reduction Method in i.MX51 Chip

作　　者：张长君[1] 曹伟[2] 

机构地区：[1]大连大学信息工程学院,辽宁大连116622 [2]辽东学院信息学院,辽宁丹东118000

出　　处：《辽东学院学报（自然科学版）》2009年第3期222-226,共5页Journal of Eastern Liaoning University:Natural Science Edition

摘　　要：i.MX51芯片是一种小型低功耗的CPU芯片,用在许多移动设备上。在发热和功耗方面都有不俗的表现,但是在有些情况下这还远远不够。文中详细讨论了CPU功耗与系统时钟的关系,采用轻量级嵌入式操作系统ECOS,对时间片调度和实时时钟系统进行了修改。即在ECOS的配置文件中关闭时间片调度机制,然后延长实时时钟的中断间隔,这样就不需要计算时间片,实时时钟的中断也不必以很高的频率产生,从而降低系统在空闲时的功耗。调度器不用定时运行,也可以节省系统功耗,使得系统在Idle状态下不被实时时钟的中断唤醒,从而大大降低系统的功耗。文中给出了实验数据:关闭时间片调度、延长实时时钟中断间隔与打开时间片调度、正常实时时钟中断间隔的功耗比约为1/10。The i. MX51 chip is a small and low -power CPU chip used in many mobile devices. It has good performance in giving out heat and power consumption, but it is far from enough in many cases. Based on description of the relationship between CPU power consumption and the system clock in detail, the authors use light embedded operating system ECOS to schedule time slice and modify real - time clock chip, that is, to close time slice scheduling mechanism in the ECOS configuration file, and then extend the real -clockg interrupt interval, thereby there is no need to calculate time slice and to generate real -clock＇s interrupt interval at a high frequency so that the system power when CPU is in idle is reduced. Besides, if scheduler does not run regularly, the system can also save power. It can make system to be not waked up by real -time clock interrupt in the idle state so as to significantly reduce system power consumption. Some experimental data related to closing time slice scheduling, extending real -time clock interrupt interval power with the opening time slice and 1/10 normal real- time clock interrupt interval power are given.

关 键 词：i.MX51芯片 ECOS操作系统 时间片调度 实时时钟 Idle状态 

分 类 号：TP306[自动化与计算机技术—计算机系统结构]