Wiki kit 32/8266 read battery voltage

Hi,

I have two ESP’s , ESP8266, by Heltec and an ESP32, also made by Heltec. I would like to make both if not one be able to read the battery level/voltage so i can be warned before it runs out. I have found this script on the Heltec GitHub, ESP32 i couldn’t find one for the ESP8266, but i am not sure how to or what to connect.

Hi, in the newest ESP32 board, there already have a battery voltage read circuit:

You can read battery voltage by using this example: https://github.com/HelTecAutomation/Heltec_ESP32/blob/master/examples/ESP32/ADC_Read_Voltage/Battery_power/Battery_power.ino