Open fire on an LED matrix display

It is winter and the right time for warm thoughts. May this LED matrix open fire help.

Parts

Circuit

Arduino LED Matrix display Max7219

The LED matrix is connected directly to the Arduino. This requires three digital pins for SPI communication and two cables for the power supply (GND and 5V +).

You can find more information on how the LED matrix works in the Tutorials section: Arduino Matrix Display 8 × 8 pixels and lots of fun.

Code

Here is the program code. The light height of the individual rows is determined.

if (int(random(1)) == 0) {
    for (int x = 0; x < 8; x++) {
      theHeightTarget[x] = int(random(5)) + 1;
    }
  }

Then the program tries to adjust the current light height.

  // update
  for (int x = 0; x < 8; x++) {
    if (theHeightTarget[x] > theHeightCurrent[x])theHeightCurrent[x]++;
    if (theHeightTarget[x] < theHeightCurrent[x])theHeightCurrent[x]--;
  }

This is then shown on the matrix.

  // show display 
  for (int x = 0; x < 8; x++) {
    for (int y = 0; y < theHeightCurrent[x]; y++) {
      lc.setLed(0, x, y, 1);
    }
    for (int y = theHeightCurrent[x]; y < 8; y++) {
      lc.setLed(0, x, y, 0);
    }
  }

Every now and then a spark is released and flies upwards.

// sparks
  sparkX = int(random(8));
  if (int(random(40)) == 0) {
    for (int y = 4; y < 8; y++) {
      if (y == 4) {
        lc.setLed(0, sparkX, y, 1);
      } else {
        lc.setLed(0, sparkX, y, 1);
        lc.setLed(0, sparkX, y - 1, 0);
      }
      delay(25);
    }
  } else {
    delay(100);
  }

Find the complete code her:

#include "LedControl.h"
LedControl lc = LedControl(12, 11, 10, 1);

int theHeightTarget[8];
int theHeightCurrent[8];

int fireHeight = 0;
int sparkX = 0;

void setup() {
  lc.shutdown(0, false);
  lc.setIntensity(0, 8);
  lc.clearDisplay(0);
  Serial.begin(115200);
}

void loop() {  
  //lc.clearDisplay(0);
  // set Heights
  if (int(random(1)) == 0) {
    for (int x = 0; x < 8; x++) {
      theHeightTarget[x] = int(random(5)) + 1;
    }
  }

  // update
  for (int x = 0; x < 8; x++) {
    if (theHeightTarget[x] > theHeightCurrent[x])theHeightCurrent[x]++;
    if (theHeightTarget[x] < theHeightCurrent[x])theHeightCurrent[x]--;
  }

  // show display 
  for (int x = 0; x < 8; x++) {
    for (int y = 0; y < theHeightCurrent[x]; y++) {
      lc.setLed(0, x, y, 1);
    }
    for (int y = theHeightCurrent[x]; y < 8; y++) {
      lc.setLed(0, x, y, 0);
    }
  }

  // spark – Funkenflug
  sparkX = int(random(8));
  if (int(random(40)) == 0) {
    for (int y = 4; y < 8; y++) {
      if (y == 4) {
        lc.setLed(0, sparkX, y, 1);
      } else {
        lc.setLed(0, sparkX, y, 1);
        lc.setLed(0, sparkX, y - 1, 0);
      }
      delay(25);
    }
  } else {
    delay(100);
  }
}

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