사물인터넷 (IoT, Internet of Things)의 최종단 장치들은 배터리로 운영되는 제품군이므로 초저전력(Ultra-low power: ULP)에 대한 세심한 고려가 필요하다. 마이크로 컨트롤러 (Micro Controller Unit: MCU) 업계는 에너지 절약을 위해 매우 효과 적인 기능을 개발해 왔으며, 제조사 별로 서로 다른 에너지 소비를 줄일 수 있는 여러가지 동작 모드를 적용하고 있기 때문에, 개발자들은 MCU 선택에 어려움을 겪을 수 있다. 따라서, 본 논문에서는 다양한 벤더 및 기능 세트의 MCU를 비교할 수 있는 표준화 된 벤치마크 방법인 ULPMark 벤치마크에 대해서 소개하고, 이 평가에서 우수한 평가를 받은 2개의 플랫폼이 초저전력 동작을 위해 제공하고 있는 하드웨어 기능에 대해서 분석하였다. 또한, 드라이버 API와 세부 레지스터 제어를 통해 개발자들이 이 기능 들을 활용할 수 있는 방법에 대해 조사하고 분석 하였다.
Since the end devices of the Internet of Things (IoT) are battery operated products, careful consideration for ultra-low power (ULP) is required. The Micro Controller Unit (MCU) industry has developed very effective functions to save energy, but developers have difficulty in selecting the MCU because various operating modes are applied to reduce energy consumption by manufacturers. Therefore, this paper introduces ULPMark benchmark, a standardized benchmark method that can compare MCUs of various vendors and feature sets, and provides hardware functions for ultra-low-power operation of the two platforms that received the high evaluation scores from ULPMark. In addition, we investigated and analyzed how developers can utilize the functions for ultra low power consumption through driver APIs and detailed register control.
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