hello, I have a 3.3v battery that supplies power to an arduino uno. I connected this battery to the Vin to bypass the builtin regulator of the arduino. I want to monitor the voltage across this battery using the arduino it supplies.
I connected A0 to positive terminal of the battery and used this code: int val; val=analogRead(0); val1 = map(val, 0, 1023, 0, 5) ; //0-5V
I get contant value of 5v, is this correct? why do I get 5V when the battery is 3.3v?