Just curious if anyone has some good experience with them besides the 8x8 matrix.
Hi... I'm trying to do the same thing... Have you gotten any replies?
Nope. I'm working on a drawing and getting it figured out. Thing is I'm making a big cube. 16 inches by 16 inches square ;).
Is that going to be 8x8x8 leds?
Title is a little confusing. A cube is three dimensional array of lights, as in 8x8x8 (512 leds), where as a 8x8 is a two dimensional matrix of lights (64 leds). Which configuration are you interested in?
Lefty
Hi... I'm building an 8x8x8 cube (512 leds)...
I'm using the LEDControl library with a 328 Arduino...
I'm using 8 max7219 chips - each powering 64 leds.
Can I use external power for the chips and leds? If so, can you let me know what I have to do? Thanks.
I'm not familiar with that chip so can't give you too much help there. By all means you will have to use an external power supply to power that many LEDs, even multiplexing.
I'm just finishing up a 5x5x5 blue diffused led cube and can give a few pointers. First be sure to use diffused leds as the super bright ones don't have a good spread to them and won't look as good, even if brighter. I got my blue diffused leds directly from Asia via E-bay at around 5 cents each when bought in bulk 100 quanities.
Also I think that any cube will have more interesting patterns if you use a odd number of leds in the matrix, such as 7x7x7 or 9x9x9, compared to 8x8x8. Even numbers will never have a 'center led' so the patterns and display scripts will not be as artistically interesting IMO.
Here is the site where I based my design from: LED Cube Matrix Driver
It uses a much better shift/driver chip in my opinion. 16 bits per chip plus it regulates the led current so you don't require external current limiting resistors, and so the display leds keep the same brightness no matter how many or few leds are lite up, that is big improvement.
My last advice is that unless you have built large cubes before, start with a smaller array for your first try. You will learn a lot that will make building a larger array in the future much less difficult and less risk of project failure. I found 5x5x5 very challenging and I've built lots of other things in the past. I think 5x5x5 is the better tradeoff between size, costs, difficulties, etc for ones first attempt.
Good luck
Lefty
I have ultrabright LEDs. I am doing a 4x4x4. Each led is going to be spaced 4 inches apart (16 inch sq). A big light ;). Anyways looking at the schematic is confusing. Do the anodes share the same ground in each column?
Do the anodes share the same ground?
Cubes can be designed for anode or cathode column drives. It depends on the type of driver chips you use and the row drivers circuitry you use. Usually one finds a schematic of a existing design to apply to their project.
Lefty
I'm going off the 8x8 schematic for the max7219 in the playground.
What's confusing me is getting it into 4x4x4.
Each row has 8. From what I'm getting in order to get a sum of 8 would be 4x2. Confused on how to wire it. Any ideas?
I couldn't find a link to the schematic you are talking about.
Lefty
Hi...
Here is a graphic that I edited so I could quickly use it for wiring up led boards... Since it references an 8x8 matrix, you can scale it down to meet your individual needs, be it 4x4 or 5x5. The pin numbers reference the actual pin locations on the max chip; 1-12, 24-13; left to right, top to bottom... So pins 17, 15, etc. are rows; pins 2,11,6 are columns.
Each row has 8. From what I'm getting in order to get a sum of 8 would be 4x2. Confused on how to wire it. Any ideas?
No I'm afraid not. That schematic is too spread out and not clear how it would be adaped for a XxXxX cube application. Sorry
Lefty
:-?
Hi... I'm trying to post a graphic... I can't seem to find any button the message board that allows me to upload an image... I tried pasting an image within the img tags - no go...
Silly question: how do you do this?
You have to get the image hosted somewhere. Then, within the image tags, paste the URL to the picture.
Bummer - so where do I send it to be hosted? What do people normally do for this?
imageshack is one place. Google for picture hosting to find others.
