Neopixel strip and Tessel

patrickm 2014-07-27 21:17:24 UTC #1

Hi!

I got a Neopixel strip, got it running with an Arduino Uno (simple sketches for colors and LED sequences).

Now, I want to try the same on the Tessel, but so far, I can't get something blinking. I tried to wire the strip with VCC +3.3V from the GPIO bank, and GPIO pin 3 from module A. The sketch is the same as in https://forums.tessel.io/t/tessel-and-breadboards/500/7

This setup looks roughly as in the screenshot.

Do you have some hints, what code to try, or what I could be missing in the schematics?

jon 2014-07-27 21:43:17 UTC #2

Hi @patrickm,

I wrote up a custom firmware build especially for Neopixels. Check out the README of the neopixels npm module for instructions on how to use it.

You can also check out this other Forum thread where @andy_mcdonald is working on getting Neopixels to work with Tessel.

Let me know if you have any questions!

Jon

patrickm 2014-07-28 09:03:04 UTC #3

Thanks! Unfortunately, I haven't got the power module, are there any options to workaround it, or I'll order that module later this week.

jon 2014-07-28 17:16:33 UTC #4

Hi @patrickm,

I recommend getting this power supply from Adafruit.

You can also use VIN on the Tessel to power the Neopixels as long as you only ever light up 5 to 10 LEDs at once. 10 LEDs will draw around 350mA and Tessel itself draws around 150mA. USB 2.0 supplies 500mA and USB 3.0 provides upwards of 900mA so you should be safe. You may see poor WiFi performance if you power it from Tessel b/c there may not be enough current for the bursts required for RF transmissions.

The Neopixels guide says you should use a 3.7V power source for a 3.3V microcontroller, but I've tried it with 5V (like VIN from USB) and it worked fine.

I hope that helps,

Jon