//Photoresistor exercise 1:
//Modify the program so that the LED shows the opposite. When there is little light, it will be bright and when there’s lots of light, it will be off.
int photoCellPin = A0;
int photoCellReading = 0; //create a variable to hold the light reading
int ledPin = D2;
int ledBrightness = 0; //create a variable to store the LED brightness
void setup() {
//setup the LED for output
pinMode(ledPin, OUTPUT);
Particle.variable("light", &photoCellReading, INT); //create a cloud variable of type integer
}
void loop() {
digitalWrite(ledPin, HIGH);
photoCellReading = analogRead(photoCellPin); //read the photo cell reading, 0-4095
int ledBrightness = map(photoCellReading, 0, 4095, 255, 0); //map this value into the PWM range (0-255) and store as led brightness
int lightreading = map (1500,0,4095,0,255);
if(ledBrightness >= lightreading){
analogWrite(ledPin, ledBrightness); //fade the led to the desired brightness
}else{
digitalWrite (ledPin, LOW);
}
delay(100); //wait 1/10th of a second and then loop
}
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