Internal voltage measuring

[beg_dk]

Hi

Before locking my interest on the ESP32, I did some testing/measuring with Esp8266 as to internal voltage. I had it solar powered by battery and therefore would like to know what was possible with esp8266. I switched to Esp32 due to Espressifs much improved developer framework and now developing in C coming from Lua believing it is more power effecient this way.

Apparently there are some differences as to accessing the internal voltage. Esp8266 just had a adc.readvdd33(); in Lua and that was it, but I can not find a similar api for doing this in esp-idf. I looks like I have to connect the vcc with a pin that must be configured to read the voltage - is that the way to go about it?

Thanks