關於 ESP8266

單獨 ESP8266, 能做甚麼? : 請看此篇文章 ESP8266 Web Server with Arduino IDE

與 Arduino 結合 : How To Use the ESP8266 and Arduino as a Webserver . 透過 UART 溝通, 可使 Arduino 具備網路遠端控制功能

可使用 Arduino IDE 直接上傳程式進 ESP8266 : Arduino core for ESP8266 WiFi chip
在其網頁下方的說明, 包含非常詳細的文件. 及 USB to serial + ESP8266 接法

Putting Device Into Flash Mode

To enable ESP8266 firmware flashing GPIO0 pin must be pulled low before the device is reset. Conversely, for a normal boot, GPIO0 must be pulled high or floating.

If you have a NodeMCU dev kit then you don't need to do anything, as the USB connection can pull GPIO0 low by asserting DTR and reset your board by asserting RTS.

If you have an ESP-01 or other device without built-in USB, you will need to enable flashing yourself by pulling GPIO0 low or pressing a "flash" switch, while powering up or resetting the module.

AT command 參考手冊 : 4a-esp8266_at_instruction_set_en from espressif