(Reference) Photoresistors
Photoresistors
Wiring
- Requires analog input pin (Pins
A0
-A5
)
Operation
- As light level varies, Argon will measure a voltage change on analog input (due to voltage divider)
- Since this is an analog input, we use analog to digital conversion to read input
- Voltage on pin will varies 0v to 3.v, and Argon will read 0 to 4095
Code
const int PIN_PHOTORESISTOR = A5;
void setup() {
Serial.begin(9600);
pinMode(PIN_PHOTORESISTOR, INPUT);
}
void loop() {
// read analog value (ADC); range 0-4095
int lightReading = analogRead(PIN_PHOTORESISTOR);
// if you want to know the actual voltage
int voltage = (float) lightReading / 4095 * 3.3;
}