Built an ESP8266 Wi-Fi logger which runs by one CR2032 coin cell. Theoretically the battery can last up to 4 months if it periodically operate one HTTP communication an hour. Wi-Fi というのは電気を食うので、コイン電池… 続きを読む »
Measured how long ESP8266 takes time connecting Wi-Fi AP since power-up. Found that it only takes 1.4 seconds to get an HTTP reply after deep-sleep wakeup if we apply IP address statically (without D… 続きを読む »
Evaluating NodeMCU firmware and also MicroPython. Key points are, we can run esptool.py with 'flash_id' command to obtain Flash size information, and also, it may help to boot ESP8266 correctly by onc… 続きを読む »
Measured ESP8266 power-down (or sleep) mode current consumption. It was about 17uA at 3.3V. Good enough! 超小型 Wi-Fi モジュール ESP8266 ですが、動作時の消費電流が大きいのが難点です。最大で数百ミリアンペア程度消費するので、電源回路を工夫しないと、小さな電池で動作させるのは困… 続きを読む »
Following the ESP8266 community, I have evaluated the small footprint Wi-Fi module too. P.S. I have reported a prototyping which runs ESP8266 with one CR2032 coin cell on Sep. 17, 2016. 今日は仕事のことは忘れて（W… 続きを読む »