controllable LED's  - Page 1
Forum section: electronics / projects

author: Simon
author_rank: Unknown
timestamp: March 06, 2014, 11:18:34 am
content: I need to do an LED setup on a plinth, 3 rows x 3 colours (9 total) so that the step bottom to top and then start again. Is there anything commercially available that is easy to configure or am I best just creating my 16 channels controlling 9 LED's each ?I've seen plenty of addressable LED strips but I'm not sure how to use these in non "christmas lights" mode

author: uwezi
author_rank: Unknown
timestamp: March 06, 2014, 07:49:27 pm
content: I suppose you are aware of the RGB LEDs with built-in WS2812 controller. These take in their information in a serial data stream which is handed down from LED to LED.http://www.adafruit.com/datasheets/WS2812.pdf

author: klr5205
author_rank: Regular Contributor
timestamp: March 07, 2014, 12:42:08 am
content: Quote from: uwezi on March 06, 2014, 07:49:27 pmAdditionally if you're not locked into a platform yet, Paul over at PJRC has a great library which allows a single Teensy development board (ARM 32bit Cortex M4) to control up to 1000 of those addressable LEDs (WS2811, WS2812, and WS2812B). Look for the video panel he made out of them for an example of their capabilites. Those LEDs are available as components or strung together in flexible strips. Search on either "neopixel" or WS2812 to learn more. They're bright and really easy to use so I'd recommend getting some to play with even if they don't perfectly fit your application.Teensy 3.1:https://www.pjrc.com/teensy/index.htmlOctoWS2811:https://www.pjrc.com/teensy/td_libs_OctoWS2811.html

author: Psi
author_rank: Super Contributor
timestamp: March 07, 2014, 12:54:19 am
content: As said, individually addressable led strips is probably the easiest.Maybe checkout sparkfun, i'm sure they sell RGB strips with all the docs and probably AVR/PIC/Arduino example code.Even if the sparkfun led strips are expensive the example code is probably for a generic control chip and you can source the strips elsewhere.

author: custompc48809
author_rank: Newbie
timestamp: March 07, 2014, 01:53:36 am
content: Hi Everyone,I decided to go out and buy some RGB LED Strips I also got a controller that allows 133 modes, well I wanted to take that strip which also has the 6803 IC 5050 LED's. I wanted to get a Audrino Uno and get some code that will allow me to turn it into a display board. Does anyone have any ideas on some code for that?

author: Simon
author_rank: Unknown
timestamp: March 07, 2014, 07:04:21 am
content: I will also be controlling this with an arduino. Given my current knowledge of AVR's I can do a simple direct address each LED by putting pins high and low in C but if I have to do any data communication with controllers I'll need to make that an arduino setup.

author: klr5205
author_rank: Regular Contributor
timestamp: March 07, 2014, 01:07:07 pm
content: You're in luck then because the adafruit neopixel library makes all that fairly simple.For example if you had a long strip and you wanted to write to only one specific pixel, the code is just:strip.setPixelColor(pixel, 32bitcolorvalue); //You can use a single 32bit value or 3 separate 8 bit values to describe RGB.strip.show(); //This clocks out the color data and latches it in the pixels. Interrupts are disabled during this and you need a minimum of a 50us delay or so before calling it again.Of course you need to do your own house keeping to get rid of pixels you don't want on anymore but its really pretty darn simple