const float GAMMA = 0.7;
const float RL10 = 50;
void setup() {
Serial.begin(115200);
Serial.println("Hello, ESP32!");
pinMode(12, INPUT);
}
void loop() {
// put your main code here, to run repeatedly:
// These constants should match the photoresistor's "gamma" and "rl10" attributes
// Convert the analog value into lux value:
int analogValue = analogRead(33);
Serial.println(analogValue);
float voltage = float(analogValue) / 4095.0 * 3.3;
float i = ((3.3 - voltage) / 10000);
float resistance = voltage*10000.0/(3.3 - voltage);
Serial.println(resistance);
float lux = pow(RL10 * 1e3 * pow(10.0, GAMMA) / resistance, (1.0 / GAMMA));
if(isfinite(lux))
{
Serial.print("The brightness is ");
Serial.print(lux);
Serial.println(" lx");
}
else
{
Serial.println("Too bright to measure");
}
delay(300);
}