I have the following setup:
* 5v Trinket
* 2m NeoPixel 60 strip (120 pixels total)
* 2500mAh 3.7v LiPo battery pack
The trinket is connected to the input end of the neopixel strip: BAT pin connected to 5v input on the strip, ground to ground, pin #1 connected to the Din input on the strip. The battery is connected to the opposite end of the strip. When connected, the power light on the trinket lights up, but none of the pixels do. I can't figure out why. Here's what I've tried:
* Loaded the Blink sketch onto the trinket to verify its working (works both with USB and LiPo power)
Other info:
* When in bootloader mode, the first pixel on the strip blinks in unison with the LED on the trinket itself
What am I missing or doing wrong?
Troubleshooting Trinket5v + 120 NeoPixel strip + 2500mA LiPo
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- mcbenton
- Posts: 5
- Joined: Mon Apr 20, 2015 12:14 am
- mcbenton
- Posts: 5
- Joined: Mon Apr 20, 2015 12:14 am
Re: Troubleshooting Trinket5v + 120 NeoPixel strip + 2500mA
Update, I can get the script to work when I change the number of pixels to 109 or lower. Is there some limit on the number of pixels that can be controlled by a trinket?
- adafruit_support_mike
- Posts: 67485
- Joined: Thu Feb 11, 2010 2:51 pm
Re: Troubleshooting Trinket5v + 120 NeoPixel strip + 2500mA
The NeoPixel library uses 3 bytes of RAM for each pixel, and a Trinket has 512 bytes of RAM. The numerical limit is around 170 pixels, but you also have to leave space for the rest of your variables.
Please be positive and constructive with your questions and comments.