const float Vref = 3.3;     // STM32 ADC reference voltage

// Voltage divider resistors (Ohms)
const float R1 = 2000.0;   // Top resistor
const float R2 = 1000.0;   // Bottom resistor

void setup() {
  Serial.begin(115200);
  analogReadResolution(12); // STM32 = 12-bit ADC
  pinMode(PA0, INPUT_ANALOG);

}

void loop() {
  int rawADC = analogRead(PA0);

  // Convert ADC reading to voltage at pin
  float Vout = (rawADC * Vref) / 4095.0;

  // Calculate original input voltage
  float Vin = Vout * (R1 + R2) / R2;

  Serial.print("ADC: ");
  Serial.print(rawADC);
  Serial.print(" | Vout: ");
  Serial.print(Vout, 3);
  Serial.print(" V | Vin: ");
  Serial.print(Vin, 3);
  Serial.println(" V");

  delay(500);
}