Realistic Fire Simulation

In this page is described how to create a realistic flickering fire effect with LEDs and an Arduino board. In this case I used a Digispark due to its small size.

int p1 = 0; // Set the 3 pins with PWM
int p2 = 1;
int p3 = 4;

void setup() {
  pinMode(p1, OUTPUT); // Set the pins as output
  pinMode(p2, OUTPUT);
  pinMode(p3, OUTPUT);
}

void loop() {
  int v1, v2, v3;

  v1 = random(155) + 100; // Calculate the new light
  v2 = random(155) + 100; // intensity values for each LED
  v3 = random(155) + 100;

  analogWrite(p1, 255 - v1); // Apply the light intensity
  analogWrite(p2, 255 - v2); // to each LED
  analogWrite(p3, 255 - v3);

  delay(20 + random(80)); // Wait some random time for next udpate
}

Demonstration: