I'm trying to get a Gemma and a NeoPixel ring working based on this tutorial http://learn.adafruit.com/superhero-pow ... t/build-it. I don't have the single neopixel so the code is adjusted to use 16 LED.
I think I short circuited a neopixel ring, since only the first 6 lights light up.
I'm wondering if I also damaged the Gemma.
I have a 2nd neopixel ring. Whenever the USB on my macbook is plugged in, all the lights are at 255,255,255. When the USB is disconnected, and it runs on battery, the lights go back to blue.
Is it possible that the Gemma is damaged and the USB is overpowering the neopixels?
Gemma and NeoPixel problems after short circuit
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Please be positive and constructive with your questions and comments.
- doncoleman
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Re: Gemma and NeoPixel problems after short circuit
Can you post a photo or two of your project?
Thanks
Thanks
- doncoleman
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Re: Gemma and NeoPixel problems after short circuit
Here's the broken neopixel ring. The sketch lights all 16 lights, but it stops at the power wire.
Here's a different neopixel ring running the same sketch.
I don't have a good picture of the Gemma, but when the power input is USB or a new battery, the pixels go to 100% white, even if they are set to red. Is there something I can measure to see if I cooked Pin 1 or the whole Gemma?- adafruit_support_mike
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Re: Gemma and NeoPixel problems after short circuit
Just to check: the device in the picture is a Flora not a Gemma. You said you don't have a good photo of the Gemma, so am I right in thinking you connected the Flora to show how the NeoPixel ring looks?
If that's correct, you can test your Gemma by loading a simple "blink an LED at 1Hz" sketch into it for each pin. Two or three voltage dividers and `analogRead()` will tell you whether the ADC is working correctly, and a voltmeter will confirm the outputs from the Vout, 3.3v, and GND pins.
WRT the ring that only lights part-way, it looks like the first non-working NeoPixel is dead.
NeoPixels use a rather neat communication protocol: each chip consumes the first 32 bits of input it sees on the data line, then copies everything else to its next neighbor. That makes life easier for a logic device controlling a string of them, but if one chip dies, the rest of the string loses its data connection.
WRT the all-white output from a strong power supply, does that happen with both rings and when running from both the Flora and the Gemma?
If that's correct, you can test your Gemma by loading a simple "blink an LED at 1Hz" sketch into it for each pin. Two or three voltage dividers and `analogRead()` will tell you whether the ADC is working correctly, and a voltmeter will confirm the outputs from the Vout, 3.3v, and GND pins.
WRT the ring that only lights part-way, it looks like the first non-working NeoPixel is dead.
NeoPixels use a rather neat communication protocol: each chip consumes the first 32 bits of input it sees on the data line, then copies everything else to its next neighbor. That makes life easier for a logic device controlling a string of them, but if one chip dies, the rest of the string loses its data connection.
WRT the all-white output from a strong power supply, does that happen with both rings and when running from both the Flora and the Gemma?
- doncoleman
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- Joined: Sat Feb 09, 2013 12:54 am
Re: Gemma and NeoPixel problems after short circuit
Yes I switched to the Flora to diagnose the NeoPixel rings.
Is there a way I can jumper around the dead NeoPixel to make the ring work again?
I'll test the Gemma like you suggest.
The all white lights when powered from USB or a fully charged https://adafru.it/1317 battery only happen on the Gemma. Everything works find on the Flora.
Is there a way I can jumper around the dead NeoPixel to make the ring work again?
I'll test the Gemma like you suggest.
The all white lights when powered from USB or a fully charged https://adafru.it/1317 battery only happen on the Gemma. Everything works find on the Flora.
- adafruit_support_mike
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- Joined: Thu Feb 11, 2010 2:51 pm
Re: Gemma and NeoPixel problems after short circuit
Sure. If you're comfortable soldering SMT components, you can remove the dead NeoPixel and replace it with one of these: http://www.adafruit.com/products/1379doncoleman wrote:Is there a way I can jumper around the dead NeoPixel to make the ring work again?
A less-officially-correct solution would be to run a jumper from the data-IN pin of the dead NeoPixel to the data-IN pin of the next one.
Hmm.. that does sound like something's wrong with the Gemma.doncoleman wrote:The all white lights when powered from USB or a fully charged https://adafru.it/1317 battery only happen on the Gemma. Everything works find on the Flora.
- doncoleman
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- Joined: Sat Feb 09, 2013 12:54 am
Re: Gemma and NeoPixel problems after short circuit
Thanks Mike.
I'll jumper around the bad pixel for now, and try replacing it later.
The Gemma is probably cooked. I have a few more on the way, so I'm not going to worry about it for now.
I'll jumper around the bad pixel for now, and try replacing it later.
The Gemma is probably cooked. I have a few more on the way, so I'm not going to worry about it for now.
- adafruit_support_mike
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Re: Gemma and NeoPixel problems after short circuit
Remember that the 'take a frame of data and pass the rest along' protocol will shift all your color values one step down the chain. If you want to keep two rings in sync with each other, you'll face a bookkeeping challenge in the code.
- doncoleman
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Re: Gemma and NeoPixel problems after short circuit
I think I tracked down the problem with the lights being very bright. It appears to be a problem with OS X 10.8 programming Gemma (and Trinket.) This page http://learn.adafruit.com/introducing-g ... rduino-ide says there's a problem with 10.9 and Adafruit Arduino IDE 1.0.5. I had the problem with 10.8. Maybe it was something with XCode 5?
The hardware works OK when I run Adafruit Arduino IDE 1.0.5 on OS X 10.7.
The hardware works OK when I run Adafruit Arduino IDE 1.0.5 on OS X 10.7.
- adafruit_support_mike
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Re: Gemma and NeoPixel problems after short circuit
I shouldn't think it was a problem with Xcode.. that's a completely different toolchain. The OS X version of the Arduino IDE has a built-in copy of gcc..
.. actually, I just checked, and it appears to have four distinct copies of gcc. Props for thoroughness I guess.
It's interesting that the problem seems to be associated with BANNED though. We know there are other things that don't quite work, so we'll mark this down as one more data point.
In the meantime, yay for having a platform that works!
.. actually, I just checked, and it appears to have four distinct copies of gcc. Props for thoroughness I guess.
It's interesting that the problem seems to be associated with BANNED though. We know there are other things that don't quite work, so we'll mark this down as one more data point.
In the meantime, yay for having a platform that works!
- metcalfepete
- Posts: 2
- Joined: Fri Jan 31, 2014 10:33 pm
Re: Gemma and NeoPixel problems after short circuit
I just recieved my Gemma and 16 LED Neo Pixel ring this morning.
I'm seeing a similar issue, only the first 5/16 LEDs is lighting up.
I'm assuming that its a short.
Can I mail the ring back, and get an exchange ?
Thanks
Pete
I'm seeing a similar issue, only the first 5/16 LEDs is lighting up.
I'm assuming that its a short.
Can I mail the ring back, and get an exchange ?
Thanks
Pete
- adafruit_support_mike
- Posts: 67459
- Joined: Thu Feb 11, 2010 2:51 pm
Re: Gemma and NeoPixel problems after short circuit
We'll need to check a few things here in the forum to build the support casefile, but if we confirm a hardware failure we'll get you a replacement. We test all our NeoPixel rings before they're approved for sale, so we need to figure out what happened between then and now.
Post a photo of your ring as you have it hooked up now (800x600 is a good size for images) along with your code (in CODE tags please).
Post a photo of your ring as you have it hooked up now (800x600 is a good size for images) along with your code (in CODE tags please).
- metcalfepete
- Posts: 2
- Joined: Fri Jan 31, 2014 10:33 pm
Re: Gemma and NeoPixel problems after short circuit
Problem solved, operator error.
My kids and I are loving the Gemma and neopixels.
Using alligators clips on the ring however proved to be tricky than we though.
The clips were shorting a pin and it looked like a failure.
Thanks for you quick response.
My kids and I are loving the Gemma and neopixels.
Using alligators clips on the ring however proved to be tricky than we though.
The clips were shorting a pin and it looked like a failure.
Thanks for you quick response.
- pburgess
- Posts: 4161
- Joined: Sun Oct 26, 2008 2:29 am
Re: Gemma and NeoPixel problems after short circuit
Not the first time. I've added a note to the NeoPixel Überguide to warn of this. Thanks for the feedback!
Please be positive and constructive with your questions and comments.