LED Cube 4x4x4

1.4M1.7K809

Intro: LED Cube 4x4x4

Amazing 3 dimensional LED display.

64 LEDs makes up this 4 by 4 by 4 cube, controlled by an Atmel Atmega16 microcontroller.
Each LED can be addressed individually in software, enabling it to display amazing 3d animations!

8x8x8 LED cube now available, by popular demand:

https://www.instructables.com/id/Led-Cube-8x8x8/


STEP 1: What You Need

First of all, you need quite a bit of time to solder together 64 leds ;)

Knowledge list:
  • Basic electronics and soldering skills
  • Know how to program an AVR microcontroller - I will not cover that in this instructable.

Component list:
  • Protoboard. The type with copper circles.
  • Atmel AVR Atmega16 microcontroller
  • Programmer to program the Atmega16
  • 64 Leds
  • 2 status leds. I used red and green. (optional)
  • Max232 rs-232 chip, or equivalent.
  • 16 resistors for leds. (100-400ohms) will get back to this.
  • 2x resistor 470 ohm. for status leds
  • 1x resistor 10k
  • 4x resistor 2.2k
  • 4x NPN transistor BC338 (or other transistor capable of switching 250-ish mA)
  • 1x 10uF capacitor
  • 1x 1000uF capacitor
  • 6x 0.1uF ceramic capacitor
  • 2x 22pF ceramic capacitor
  • 1x crystal 14.7456 MHz
  • 2x tactile button
  • optional pwr switch
  • connector for 12v power
  • optional connector for 5v power

STEP 2: Multiplexing

How to control 64 LEDs without using 64 individual wires? Multiplexing!

Running a wire to the anode of each led would obviously be impractical, and would look really bad.
One way to get around this, is to split the cube into 4 layers of 16x16 LEDs.

All the LEDs aligned in a vertical column share a common anode (+).
All the LEDs on a horizontal layer share a common cathode (-).

Now if i want to light up the LED in the upper left corner in the back (0,0,3), I just supply GND (-) to the upper layer, and VCC (+) to the column in the left corner.

If i only want to light up one led at a time, or only light up more than one layer at the same time.. this works fine.

However, if I also want to light up the bottom right corner in the front (3,3,0), I run into problems. When I supply GND to the lower layer and VCC to the front left column, I also light up the upper right led in the front (3,3,3), and the lower left LED in the back (0,0,0). This ghosting effect is impossible to workaround without adding 64 individual wires.

The way to work around it is to only light up one layer at a time, but do it so fast that the eye doesn't recognize that only one layer is lit at any time. This relies on a phenomenon called Persistence of vision.

Each layer is a 4x4 (16) image.
If we flash 4 16 led images one at a time, really fast, we get a 4x4x4 3d image!

STEP 3: Making the Cube, Template

Soldering grids of 4x4 LEDs freehand would look terrible!
To get 4 perfect 4x4 grids of LEDs, we use a template to hold the them in place.

I wanted to make the cube as easy as possible to make, so I chose to use the LEDs own legs as much as possible. The distance between the lines in the grid was decided by the length of the LED legs. I found that 25mm (about an inch) was the optimal distance between each led (between the center of each led that is!) to enable soldering without adding or cutting wire.

  • Find a piece of wood large enough to make a 4x4 grid of 2,5cm on.
  • Draw up a 4x4 grid of lines.
  • Make dents in all the intersects with a center punch.
  • Find a drill bit that makes holes small enough so that the led will stay firmly in place, and big enough so that the led can easily be pulled out (without bending the wires..).
  • Drill the 16 holes.
  • Your ledcube template is done.

STEP 4: Making the Cube, Solder the Layers

We make the cube in 4 layers of 4x4 leds, then solder them together.

Create a layer:
  • Put in the LEDs along the back and along one side, and solder them together
  • Insert another row of LEDs and solder them together. Do one row at a time to leave place for the soldering iron!
  • Repeat the above step 2 more times.
  • add cross bracing in the front where the led rows are not connected.
  • Repeat 4 times.

STEP 5: Making the Cube, Connecting the Layers

Now that we have those 4 layers, all we have to do is to solder them together.

Put one layer back in the template. This will be the top layer, so choose the prettiest one :)

Put another layer on top, and align one of the corners exactly 25mm (or whatever distance you used in your grid) above the first layer. This is the distance between the cathode wires.
Hold the corner in place with a helping hand and solder the corner anode of the first layer to the corner anode of the second layer. Do this for all the corners.

Check if the layers are perfectly aligned in all dimensions. If not bend a little to adjust. Or re-solder of it's the height distance that's off. When they are perfectly aligned, solder the remaining 12 anodes together.

Repeat 3 times.

STEP 6: Choosing Resistor Values

There are two things to keep in mind when choosing a resistor value for your leds.
1) The LEDs
2) The AVR

The AVR has a maximum combined current rating of 200 mA.
This gives us 12mA to work with per LED.

You also don't want to exceed the maximum current your leds are rated to.

I used 220 ohm resistors on my cube. This gave me about 12mA per led.

STEP 7: The Controller

The circuits controlling the led cube is described in the attached schematic image.

The RS-232 interface is optional. and can be omitted. That is IC2 and all the components connected to it. Future firmwares will enable PC communication..

Start by laying out all the components on you circuit board in a layout that enable all the components to connect with a minimal amount of wires. If everything fits, solder the circuit.

I won't give any more instructions on this, as the circuit probably will look very different from cube to cube, depending on the size of the circuit board etc..

Information on how to wire the cube to the controller circuit is in the next step.

STEP 8: Wire Up the Cube

Pictures explain this better than words. Please see the pictures.

STEP 9: Compile and Program

You now have a led cube. To make use of it, it needs some software.
I have made a driver for rendering a 3d data space on the cube, and functions to display some cool visual effects on the cube.

You can use my code, write your own or build on my code and make more effects.
If you make your own effects, please send me the code. I'm eager to see what you guys make!

To compile the program. Just open a command promt,
enter the directory with the source code
type "make" on the command line.

If you want to use an ATMega32 instead of the ATMega16, just change the mcu setting in the Makefile and recompile (type make). If you use the m32 and don't do this step, the cube won't boot properly (the red and green lights will keep blinking forever).

You should now have a file named main.hex in the source directory.
The next step will show you how to get that code into your cube.

STEP 10: Program the Microcontroller

If you are experiencing problems with speed and/or some LEDs not lighting up. Please read this step carefully.

To program the microcontroller, I use avrdude and the USBTinyISP programmer.

My examples will be on an Ubuntu Linux system. The procedure should be pretty much identical on Windows, but I can't help you with that. If you use another programmer, read thet manual for that programmer and avrdude.

First off, Let's just see if we can make contact with the AVR.

Connect the programmer to your cube and your computer.

The command is "avrdude -c usbtiny -p m16", wherer -c specifies the programmer, and -p the AVR model. You can see the output in the images below.

Now, upload the firmware: "avrdude -c usbtiny -p m16 -U flash:w:main.hex".

By now, the cube should reboot and start doing stuff. It will be running at 1mhz (very slowly) using it's internal oscillator. And some of the leds won't work, because some GPIO ports are used for JTAG by default.

To enable the external oscillator and disable JTAG, we need to program the fuse bytes:
run "avrdude -c usbtiny -p m16 -U lfuse:w:0xef:m"
and "avrdude -c usbtiny -p m16 -U hfuse:w:0xc9:m".

Be carefull when doing this step! If you get it wrong, you can permanently destroy your microcontroller! If you are using another microcontroller than the ATMega16, be sure to read the datasheet carefully before changing the fuse bytes!

After writing the correct fuse bytes, the cube should reboot and start operating at regular speed with all leds operational.

Enjoy your new cube :D

STEP 11: Go Large - 8x8x8

After making this quite fancy 4x4x4 cube, I have also made an enormous 8x8x8 cube. I'll make an instructable for that one when I have time. Meanwhile, see pictures :-)

You can find the 8x8x8 version here: https://www.instructables.com/id/Led-Cube-8x8x8/

Please rate this instructable if you like it! :)


792 Comments

Is it possible to make this 4x4x4 cube with an arduino uno?
I am slightly confused as to what the RS232 does. Could you explain that?

Can I not use the voltage regulator and the Max232 chip. If I don't use them will the cube still work?

I try connect my atmel16 second time, but...Could not find usbtiny device (0x1781/0xc9f)?
I'm doing science fair. Do you know what is the dependent and independent variable in this project?
Hello, what must be Lock Bits?

Helloloo!

I am trying to build a similar grid but heating elements instead of LEDs. Other than the voltage needed and so, do you think it would work inprinciple ?

ps. I am new in building circuitry so on

THANKS

instead of voltage, you might want to be more concerned about the current required. To answer your question though, yes. The same type of principles can be applied to heating elements as well as long as you can find chips that work with your elements.

what are the black things below the board called? To keep it off the table.

Hello!
Tell me, please, the code is written in C or C++?

It is written in C

I built my ledcube thanks to your awesome tutorial, but saw this "To compile the program, open a command prompt, enter the directory with the source code and type "make" on the command line. You should now have a file named main.hex in the source directory" I tried that with the source files and I get all kinds of errors. C:\WinAVR-20100110\xledcube>make

0 [main] sh 2156 sync_with_child: child 1572(0x14C) died before initializa

tion with status code 0xC0000142

670 [main] sh 2156 sync_with_child: *** child state waiting for longjmp

/usr/bin/sh: fork: Resource temporarily unavailable

-------- begin --------

avr-gcc (WinAVR 20100110) 4.3.3

Copyright (C) 2008 Free Software Foundation, Inc.

This is free software; see the source for copying conditions. There is NO

warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Compiling: main.c

avr-gcc -c -mmcu=atmega16 -I. -gdwarf-2 -DF_CPU=14745600UL -Os -funsigned-char

-funsigned-bitfields -fpack-struct -fshort-enums -Wall -Wstrict-prototypes -Wa,-

adhlns=main.lst -std=gnu99 -MD -MP -MF .dep/main.o.d main.c -o main.o

In file included from main.c:74:

draw.c: In function 'setplane':

draw.c:170: warning: comparison between pointer and integer

draw.c:170: warning: comparison with string literal results in unspecified behav

ior

..... long list down. What is the problem ? I want to try this to remove some of the effects. I already uploaded the hex file but I want fewer effects.

Having the same problem was this ever solved?

anyone have C code for cube

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