Datasheet

After the install process, you should see that esp8266 package is marked INSTALLED. Close the Boards Manager
window once the install process has completed.
Setup ESP8266 Support
When you've restarted, select Adafruit HUZZAH ESP8266 from the Tools->Board dropdown
80 MHz as the CPU frequency
You can keep the Flash Sizeat "4M (3M SPIFFS)
For Upload Speed, select 115200 baud (You can also try faster baud rates, we were able to upload at a blistering
921600 baud but sometimes it fails & you have to retry)
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