DVS Technology And Its Application In The Total Station Equipment

With the growth of chip density and performance requirement, the embedded system power consumption grow exponentially, but stands out the problem of high energy consumption of portable instruments with dry batteries. Ensuing problems limit the development of embedded products, like increasing cost of chip cooling and decrease of chip stability. And hence, cutting down power consumption becomes one of the key aspects of portable design. Total station device is the electronic station is powered by dry batteries and integrates such functions as measurement, calculation and display together. The high power consumption generated by system operation limits the time of devices' outwork. Letting down power consumption of the total station can prolong operation time of this device, and reduce delay time caused by the problem. DVS is software of low-energy consumption supported by hardware, which dynamically adjusts the processor Implementation voltage, decreasing system energy consumption by extending operation time of the tasks. At current, the studies of DVS, mainly based on theoretical calculation, rarely applied in embedded products .This paper studies the real-time DVS algorithms, and applies it to total station equipment, which effectively solves the power consumption problem of total station equipment. This thesis mainly discusses the following points.(1)Firstly, the theoretical foundation of DVS's low energy consumption is made through analysis of CMOS integrated circuit. On the basis of adjustable voltage of processor, this paper elaborates DVS' low consumption technological structure of operation systems or compiler, the theoretical gives the theoretical basis of DVS technology for low power consumption(2)In addition, in light of the requirements of low power consumption of total station system, the paper analyzes the strengths and weaknesses of two real-time DVS algorithms: LEFD and Weiser. With deep analysis of design elements of total station system'DVS algorithm and elaboration of OPTASTS algorithm principles, and due underutilization of dynamic free time of OPTASTS algorithm and the feature of static task of total station's real-time system, the paper puts forward improved algorithm based on revision of processor's utilization, and testifies the effectiveness on the platform of SkyEye.(3)Finally, in combination of the software and hardware environment of total station system, the paper designs DVS low energy consumption technological structure of operational framework guiding with the operating system, realizes the low energy consumption management driver based on PXA250 processor; in light of the improvement OPTASTS algorithm, the paper revises task management service ofμC/OS-II, design and implementation of the EDF scheduling mechanism Besides, it realizes the improved OPTASTS algorithm of total station system. Through analysis of data, it is proved that DVS technology effectively decreases energy consumption of total station system.