// Define a pin that we'll place the photo cell on
// Remember to add a 10K Ohm pull-down resistor too.
int photoCellPin = A0;
// Create a variable to hold the light reading
int photoCellReading = 0;
// Define a pin we'll place an LED on
int ledPin = D2;
// Create a variable to store the LED brightness.
int ledBrightness = 0;
void setup()
{
// Set up the LED for output
pinMode(ledPin, OUTPUT);
// Create a cloud variable of type integer
// called 'light' mapped to photoCellReading
Particle.variable("light", &photoCellReading, INT);
}
void loop()
{
// Use analogRead to read the photo cell reading
// This gives us a value from 0 to 4095
photoCellReading = analogRead(photoCellPin);
// Map this value into the PWM range (0-255)
// and store as the led brightness
ledBrightness = map(photoCellReading, 0, 4095, 0, 255);
// fade the LED to the desired brightness
analogWrite(ledPin, ledBrightness);
// wait 1/10th of a second and then loop
delay(100);
}
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