Hi! Just bought WS2811 type strip of lights http://ebay.to/2icZpfa and started using FastLed with Arduino Mega to get them working. I wrote a simple script for it http://pastebin.com/RmMqKcgn . However, after connecting them, nothing lights up. But if I touch the ground wire at the end of the lights with the data wire at the beginning of the lights, the lights will go crazy and after separating those wires the lights light up as it should be (not all though, few of them are different color, but hey, its something!). What do I do wrong? Maybe I should connect some resistor to the data pin? Or maybe I just got broken lights?
Also I checked with multimeter the begining and the end of the wire. On power and ground cords there is only 1ohm, while data wire has 900ohm resistance. Not sure if it should be like it, so just pointing it out.
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Do you have the ground from your power supply connected to the ground of the LED string?
what colour wires do you have?
@Mantvydas_Rimsa – On your first pixel, is there an arrow pointing up on the side with the wires that are connected to your power and MCU? In other words, are you connected to the first pixel or the last pixel? Next look at the markings below this arrow on the pc board of the pixel, it will show you which wire is V+, data in and ground. On my WS2811 strings with all black wires, it is V+, data in and ground. The ground wire is the wire on the right when you are looking down at the pixel with the arrow pointing up. It might be different with your string. Finally, try changing your data pin to another pin like pin #6. Make sure that this pin is a data pin and not an analog pin on your MCU.
Some LEDs have clearly visibly arrows, this is the start of the chain, and data flows IN from this end.
In this set, the
Red = +
Blue = -
White = DATA
missing/deleted image from Google+
@Stuart_Taylor Yeah, there are also written “+”, “GND” and “DI” (red, white and green) pins, I connected them accordingly to the power supply and arduino.
@Jason_Coon Yeah, I connected + and ground from power supply to the leds. Also: if I use power straight from Arduino, sometimes it works, sometimes leds are blinking, sometimes nothing works. Seems like I am running out of power. But the problem persists even if I lower the brightness. Also leds doesnt work at all if i connect it from external 5v 10A power supply. Seems like my supply doesn’t work, but I measured it with multimeter and turns out it works like it should.
@Ken_White There is no arrow, tried to connect from both ends.
Tried 11, 10, 6 and 2 pins, no difference
Btw: is it normal that the data wire between first and last pixel has 900ohm resistance? Or my leds are just defected?
@Mantvydas_Rimsa sorry, meant to ask if you have all the grounds connected together: power supply, LEDs, and Arduino. Not sure about the resistance, but I’ll try to check later.
@Mantvydas_Rimsa please post your code to http://gist.github.com and post the gist link here.
Which pin of the mega are you using for DATA?