I have 500+ of these puppies, a lot of time on my hands.. I'm considering making an 8x8x8 matrix of these. 1) I'm planning on doing these all as one single circuit- good idea? insane?
2) If that seems not on the far side, do I wire them as horizontal layers, or vertical ones
I will be using the FASTLED libraray... just want to make sure that I wire them the best way for controlling them..
I've googled, and only see diagrams for the older LEDs with leads for each colour, and these puppies have datain - dataout If I'm going to spend this much time soldering these puppies, I'd like to get it correct the first time..
I'm probably going to go blind, they are individual small circles.. I'll have to solder 4 leads to each LED. call me crazy, but it going to be a labour of love...
so data line... I'm thinking for programming purposes.. doing row1, leds 1-8, then run a diagonal data line back to row 2, leds 1-8.. and so forth for all 8 rows of layer 1, then repeat for each layer...
this opposed to doing a snake pattern row 1 leds 1-8, row 2 leds 8-1, and so forth..
good idea or not? I just trying to make it somewhat logical for programming purposes, or am i missing something.
sammiam:
I'm probably going to go blind, they are individual small circles.. I'll have to solder 4 leads to each LED. call me crazy, but it going to be a labour of love...
So if they are individual LEDs then you need to solder a 0.1 ceramic capacitor across the power and ground of each one. You will find these already fitted on the strips.
Forget the logical programming part affecting the wiring just have the most convenient way of wiring it which is a serpentine raster. In the software you will write a simple function that takes in the three dimensional coordinates and returns an LED number.
I had a similar idea. I was less ambitious and planned to build a 4x4x4 using the ws2812b that you can buy mounted on tiny round PCBs. These have the cap already on them. Yes, 4 wires per led is a lot of soldering, but the same number as conventional RGB leds. And with the ws2812 there is no complex multiplexing driver circuit to build.
The reason I have not started is that I cannot decide on a wiring strategy. I spent hours drawing diagrams trying to figure out something that was neat and elegant, but not found it yet. I considered making all the vertical column wires +5V, the north-south horizontal wires 0V and the east-west would be data wires, in some serpentine pattern just like Mike was suggesting. I also considered making half the vertical wires 5V, half 0V, either in alternating rows or in a chessboard pattern. I kept having new ideas that looked great in my head but when I draw them on paper I realise it does not work out as tidily as I imagined, and turns out to be a bit of a mess.
It's an interesting intellectual puzzle for me. I don't want to build the thing until I come up with a design I am happy with. I would be interested to see what approach you take.
I've seen some here at Looking Glass, that were 8x8x8 cubes. They used strips of rigid, transparent PCB with the LEDs soldered on, and those were placed in connectors at the bottom of the cube. So basically all wires went vertical only. Very easy to put together. I recall they told me they were open sourcing the thing but on their web site I can't find it.
These cubes look awesome! They had a few scattered around the office, and I'm sure they had some around that were quite a bit larger than the 8x8x8 (and some 2D ones based on the same principle).
Power: Yes, it's probably good to distribute power in a tree form instead of running one wire linearly through all LEDs. Do layers then columns maybe. Or run big power wires up the corners and distribute from there into the center.
Data: If you have 8 data pins sending data to 8 layers, can you send that data simultaneously? With most Arduinos I would say the answer is "no". But it may depend on the library you're using. If the library+hardware can only send out data one layer at a time then there's no advantage in wiring the layers independently.
Well, I've abandon this project.. the LEDs that I purchased were cheapo's and after a couple of weeks of running well, started behaving erratically... Lesson learned.. don't be all that cheap with electronics.. found out later from the web that I wasn't the only one who got burnt by getting these LEDs...