Adafruit Neopixel is compatible

[posicat]

I just downloaded the code for the Adafruit neopixel LED strip and put it on one of my Digisparks, it works perfectly without modification (I ran the strandtest sample code).  I was driving an almost 1m long strip (I stole 2 of the LED's for another project) powering the strip and the Digispark off of 4.5v (3x AA batteries) without any issue.

Just thought I'd pass that along for anyone who was wondering.

PosiCat

[lecreate]

Good to know. I just purchased the NeoPixel 8 RGB LED strip for a small project and though the digispark would be a perfect application. Thanks for sharing!

[cpldcpu]

You can also use my lightweight WS2812 library to control Neopixel/WS2812 LED strips. Compared to the neopixel lib it uses a lot less memory.

https://github.com/cpldcpu/light_ws2812

[TimO]

I'm planning on trying to use one of the eight pixel units with a Digispark, to create a very simple bicycle POV unit.  Basically this is a strip of LEDs on a bicycle spoke, with the pattern changed as the wheel rotates, so Persistence Of Vision (POV) lets your create images on the wheel.

I think I can get away with mounting a small battery and the Digispark on the hub, and then just cable tie the NeoPixel to a spoke.  Very rough and ready, but enough to experiment with.  If it works, I may expand upon the number of LEDs, and waterproof things!

With no wheel synchronisation, I'll be limited to pretty coloured patterns, but with a reed switch on the wheel, and magnet on the frame, I should be able to do more complicated images, such as scrolling text messages.

[TimO]

I just plugged this all in and tried out the Adafruit test example, and it worked flawlessly!  I guess it's as much about how ridiculously easy it is to wire this up, three wires from the DigiSpark with +5V, GND and data, and you're done!

The only issue I have, is that with the Adafruit 8 NeoPixel stick, it's so bright, that it's hard to look at!  Not really a problem when I need to use it, but a pain when playing with it under normal room lighting.

[dougal]

@TimO: Save your eyeballs with this global maximum brightness setting:

Code: [Select]

strip.setBrightness(127); // for half-strength. Try lower values if needed to find your comfort level.
Voila!

[TimO]

LOL, yes that would make sense, although I'm considering stripping the code down to its bare minimum, so I can fit as much as possible into a DigiSpark, so the global brightness may go.  Once it's all spinning on a wheel, it'll probably dim the image out a bit anyway, and I may also reduce the brightness in an attempt to allow more LEDs to be illuminated simultaneously and/or increase battery lifetime.  If it's too bright for prototyping, I'll just use compiler directives to switch between a full and reduced brightness version.

[marcmerlin]

For anyone looking, the adafruit neopixel lib does work unmodified on both the original digispark (ATtiny85) and the digispark pro (ATtiny 167), however the digispark is so starved in RAM that you can only define around 100 pixels in your neopixel strand, or the chip will run out of RAM and nothing will light up.