Chipkit Uno and LDR warning example

This example is like a dark activated alarm using an LDR and a LED, in this case when the value read in drops below a certain level the LED will light. In the real world you could make a dark activated night light or alarm.

Its a fairly basic circuit, I connected the LED to D8, no real reason. LDR still connects to A0

Schematic and Layout

Chipkit and LDR and LED_schem Chipkit and LDR and LED_bb

Code

int sensorPin = A0; // select the input pin for the ldr
int ledPin = 8; // select the pin for the LED
int sensorValue = 0; // variable to store the value coming from the sensor
 
void setup() 
{
  pinMode(ledPin, OUTPUT);
}
 
void loop() 
{
  sensorValue = analogRead(sensorPin);
  if(sensorValue <= 400)
  {
    digitalWrite(ledPin, HIGH);
    delay(500);
  }
  else
  {
    digitalWrite(ledPin, LOW);
  }
}
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