The assembly of the cube:

First of all, we need a moderately thick cardboard or wood. Now we drill holes in them so that a 4 × 4 cube pattern is created with equal distances between all the holes.

5mm holes (each hole is 2.4 cm from the next (center-center)) were drilled as a template for the LEDs.

Now you need to test and prepare your LEDs. You can use a 3V button cell for this purpose. Test all the LEDs so that you don't have any problems later!

If you want the light to come out from all sides of the LED, you can diffuse the light by rubbing the plastic shell with sandpaper.

Place the LEDs in the box, but be careful about their orientation. The positive pins of the LEDs have to be bent and the negative pins connected like a layer. That's because we're going to make four such layers and it's easy to solder them together.

We repeat these layers 4x and finish them on top of each other, connecting all + pins and placing them on top of each other.

The board, pinout and connections:

in my case I chose the following pinout to control the cube like in a matrix:

You should make these connections and pay attention to the correct choice of pins, otherwise the animation will not run correctly later.

I designed the circuit board as follows and should only give you an idea of how the layout might look:

Here is the needed code!

//LED-Cube 1.0
//Niklas Heinzel
//2021


  int layer[4]={A3,A2,A1,A0}; //initializing and declaring led layers
  int column[16]={13,12,11,10,9,8,7,6,5,4,3,2,1,0,A5,A4}; //initializing and declaring led rows
  int time = 250;


void setup()
{

  for(int i = 0; i<16; i++)
  {
    pinMode(column[i], OUTPUT);  //setting rows to ouput
  }

  for(int i = 0; i<4; i++)
  {
    pinMode(layer[i], OUTPUT);  //setting layers to output
  }

  randomSeed(analogRead(10));  //seeding random for random pattern
}

void loop()
{
  turnEverythingOff();
  flickerOn();
  turnEverythingOn();
  delay(time);
  turnOnAndOffAllByLayerUpAndDownNotTimed();
  layerstompUpAndDown();
  spiralInAndOut();
  turnOnAndOffAllByColumnSideways();
  delay(time);
  aroundEdgeDown();
  turnEverythingOff();
  randomflicker();
  randomRain();
  diagonalRectangle();
  goThroughAllLedsOneAtATime();
  propeller();
  spiralInAndOut();
  flickerOff();
  turnEverythingOff();
  delay(2000);
}


//turn all off
void turnEverythingOff()
 {
   for(int i = 0; i<16; i++)
   {
     digitalWrite(column[i], 1);
   }
   for(int i = 0; i<4; i++)
   {
     digitalWrite(layer[i], 0);
   }
 }

//turn all on
void turnEverythingOn()
{
  for(int i = 0; i<16; i++)
  {
    digitalWrite(column[i], 0);
  }
  //turning on layers
  for(int i = 0; i<4; i++)
  {
    digitalWrite(layer[i], 1);
  }
}
//turn columns off
void turnColumnsOff()
{
  for(int i = 0; i<16; i++)
  {
    digitalWrite(column[i], 1);
  }
}
//flicker on
void flickerOn()
{
  int i = 150;
  while(i != 0)
  {
    turnEverythingOn();
    delay(i);
    turnEverythingOff();
    delay(i);
    i-= 5;
  }
}
//turn everything on and off by layer up and down NOT TIMED
void turnOnAndOffAllByLayerUpAndDownNotTimed()
{
  int x = 75;
  for(int i = 5; i != 0; i--)
  {
    turnEverythingOn();
    for(int i = 4; i!=0; i--)
    {
      digitalWrite(layer[i-1], 0);
      delay(x);
    }
    for(int i = 0; i<4; i++)
    {
      digitalWrite(layer[i], 1);
      delay(x);
    }
      for(int i = 0; i<4; i++)
    {
      digitalWrite(layer[i], 0);
      delay(x);
    }
    for(int i = 4; i!=0; i--)
    {
      digitalWrite(layer[i-1], 1);
      delay(x);
    }
  }
}
//turn everything on and off by column sideways
void turnOnAndOffAllByColumnSideways()
{
  int x = 75;
  turnEverythingOff();
  //turn on layers
  for(int i = 0; i<4; i++)
  {
    digitalWrite(layer[i], 1);
  }
  for(int y = 0; y<3; y++)
  {
    //turn on 0-3
    for(int i = 0; i<4; i++)
    {
      digitalWrite(column[i], 0);
      delay(x);
    }
    //turn on 4-7
    for(int i = 4; i<8; i++)
    {
      digitalWrite(column[i], 0);
      delay(x);
    }
    //turn on 8-11
    for(int i = 8; i<12; i++)
    {
      digitalWrite(column[i], 0);
      delay(x);
    }
    //turn on 12-15
    for(int i = 12; i<16; i++)
    {
      digitalWrite(column[i], 0);
      delay(x);
    }
    //turn off 0-3
    for(int i = 0; i<4; i++)
    {
 digitalWrite(column[i],...