Gemma M0 not working with Flora RGB Smart NeoPixel (v2)

[davidbesley]

Hello. I'm using alligator clips, a 3.7 v battery, Gemma M0, and have tried multiple sample codes, including that for gemma hoop earings (https://learn.adafruit.com/gemma-hoop-e ... ython-code) and I cannot get the Flora NeoPixel to light up. I have tried different Flora NeoPixels and a different Gemma M0 and that has not been effective, so I don't think it's either of these components. Any thoughts? Please see attached photos of the setup.
Thanks!
David

Gemma M0

IMG_0312.JPEG (590.99 KiB) Viewed 750 times

Flora RGB Smart NeoPixel v2

IMG_0313.JPEG (435.79 KiB) Viewed 750 times

[adafruit2]

watch out that green alligator clip is not touching any compontne it should just be at the tip of the sewing tap
try powering from 3Vo rather than Vout?

[gogaman]

@Admin, I had a similar issue with my NeoPixel (v2) where it would not run stable, but after I read your comment and after switching the VCC from VOUT to 3.3V, it seems to work stable. Why is that happening? The spec on NeoPixel (v2), says to power from 5V -> 9V. why going below spec makes things stable?

[danhalbert]

When the NeoPixel is being powered by 3.3v, then it's expecting logic levels at that voltage, and will reliably. Power NeoPixels at 5V and trying to use 3.3V logic can be problematic, since it's at the edge of the spec for the logic signals.