I have AI-Thinker ESP32-cam module and I want to measure battery level. I can do it with voltage divider (analog pin) or with INA219 sensor (I2C pins). But I do not know if it is possible with ESP32-CAM. In datasheet there is nothing about ADC pin or I2C. Does anyone have any experience? Thank you.
You can use all GPIOs of the header on the button side as analog inputs (12-15,2,4). You can define any GPIO pair as your I2C pins, just specify them in the Wire.begin() call.
One can, also, define the I2C pins using the ESP32 I2C API.
I've the same issue.
Having a look to the schematic, the pins on the button side are, except the HS2 CLK GPIO14 and HS2 DATA2 GPIO12, pulled up with 47k.
And if a SD-Card is avail, they are connected to the SD-Card.
So as analog input only 12 and 14 are useable, right ?
Finally I found the solution:
ADC1 is not available when using WIFI. So the GPIO12 and 14 cant be used as analog input while doing wifi.