I am currently in the final stages of building an LED table - the

(Dave Morgan) #1

I am currently in the final stages of building an LED table - the basic idea for which I got from an Instructables post.

In my case I’m using LPD8806 LED strips driven by a DigiX. The main grid is done and working. I have the strips for the legs mounted but not yet wired to the DigiX. Now I’m wondering the best way to accomplish that.

The DigiX has plenty of pins, but I’m using hardware SPI for the main grid and I think the DigiX only has one set of SPI pins. My thought was to wire each of the leg strips to a different set of pins (thinking that this might make programming easier or more flexible) but I don’t know if this will be possible for SPI strips.

This is the first project I’ve done with more than one contiguous strip so I don’t know what options I have. Does anyone have some suggestions for me?

I last worked on this around the beginning of the year, but I think I’m using a build of FastLED 3.1 which has support for parallel outputs.

(Daniel Garcia) #2

The FastLED parallel output is only for 3-wire led chipsets like the WS2812/NeoPixels.

You can use non-hardware SPI pins for writing to the LPD8806’s, FastLED will use hardware SPI where it can and bit-bang when it can’t.

(Dave Morgan) #3

Ok - that helps. There are only 16 LEDs per leg, so I don’t need much in the way of data rates. How do I go about determining which pins I can use? Does FastLED only support certain ones, or can I just use any available pins? Also, I presume I will need a clock and data pin pair for each strip? And finally, do I need analog, or digital pins?

(Daniel Garcia) #4

You do need a clock and data pair for each strip, and you should be able to use any pins. If you’re using analog pins, look up what their corresponding digital pin number is, though, honestly, the digix has so many pins :slight_smile: (I do think there are some analog pins that can’t be used as digital pins, but don’t quote me on that)

(Dave Morgan) #5

Great - that should get me going. Thanks Daniel!

(Philippe Charest) #6

Regarding the table light baffle I strongly suggest not to use them… It makes patterns more appealing. I built my table using baffles and removed them later… A lot of wasted time.

(Dave Morgan) #7

I personally like the look of the baffle but I can see both sides. Thanks @marmil . I’ll try to post some photos or video of my actual table when it’s done.

(Dave Morgan) #8

Here is a video of the finished table. The patterns are just a few very basic ones that I wrote long ago while the table was still being built. Now that I have a better way to see the output, I’ll create some nicer ones.

(Philippe Charest) #9

@Dave_Morgan looks good.

(Marc Miller) #10

Sweet, great job. Thanks for the video.