Implemented a native tweet bot which runs MicroPython + ESP8266. No intermediate server (which is converting requests to Twitter API) is required. SSL, HMAC-SHA1 and OAuth are all running on ESP8266. というわけで、MicroPython + ESP8266 で Twitte… 続きを読む »
Confirmed that MicroPython 1.8.4 on ESP8266 has (even limited) SSL support and could connect to google.com and also api.twitter.com by ‘https://’ prefix. ESP8266 + MicroPython による SSL の情報をネット上で探してみたのですが、なかなかまとまった情報がなくて苦労しました。こうい… 続きを読む »
Implemented “snooze mode” to reduce wake-up frequency. In other words, it goes to sleep again (N – 1) times an N wake-ups. 先日、ESP8266 を CR2032 コイン電池ひとつで動かす試作ボードを作りましたが、実際のところ、植木の水分測定のようなアプリケーションでは一日に 24回も「起き出す」必要はありません。一日… 続きを読む »
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、コイン電池で動かすには難ががあると考えられていますが、試みとして、ESP8266 をコイン… 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 DHCP)! まずは DHCP を使ってみる。これだと遅そう ESP8266 マイ… 続きを読む »
I didn’t find clear description, on the Internet, how many characters iPhone VPN can use for a pre-shared key (shared secret). I found a 32-letters key was okay but found a caveat too. (I.e. we need to restart iPhone when something … 続きを読む »