NEO PIXEL WILL NOT LIGHT

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1885
 
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Joined: Sun May 24, 2009 2:12 am

NEO PIXEL WILL NOT LIGHT

Post by 1885 »

I'm using this code to try to drive an 8 stick neo pixel.
The led is flashing on pin 13.
Arduino pin 6 is going to neo pixel DIN
5vdc from arduino is going to 5 vdc on the NEO
Ground is from the arduino next to the 5V on the arduino and I jump the ground on a bread board.
I soldered headers on the NEO and plugged it into a breadboard.
I used a multi tester and I am not getting 5v on the other end of the NEO.
No lights. Any ideas.

Code: Select all

// NeoPixel Ring simple sketch (c) 2013 Shae Erisson
// released under the GPLv3 license to match the rest of the AdaFruit NeoPixel library
#include <Adafruit_NeoPixel.h>

// Which pin on the Arduino is connected to the NeoPixels?
#define PIN            6
int led = 13;

// How many NeoPixels are attached to the Arduino?
#define NUMPIXELS      8

// When we setup the NeoPixel library, we tell it how many pixels, and which pin to use to send signals.
// Note that for older NeoPixel strips you might need to change the third parameter--see the strandtest
// example for more information on possible values.
Adafruit_NeoPixel pixels = Adafruit_NeoPixel(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);

int delayval = 500; // delay for half a second

void setup() {
  pixels.begin(); // This initializes the NeoPixel library.
    pinMode(led, OUTPUT);   
}

void loop() {
    digitalWrite(led, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(1000);               // wait for a second
  digitalWrite(led, LOW); 
  // For a set of NeoPixels the first NeoPixel is 0, second is 1, all the way up to the count of pixels minus one.
  for(int i=0;i<NUMPIXELS;i++){
    // pixels.Color takes RGB values, from 0,0,0 up to 255,255,255
    pixels.setPixelColor(i, pixels.Color(255,255,0)); // Moderately bright green color.
    pixels.show(); // This sends the updated pixel color to the hardware.
    delay(delayval); // Delay for a period of time (in milliseconds).
  }
}

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pburgess
 
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Joined: Sun Oct 26, 2008 2:29 am

Re: NEO PIXEL WILL NOT LIGHT

Post by pburgess »

The 5V trace on the NeoPixel stick is a contiguous piece of copper...if you're not measuring 5V at the output end, it's not getting 5V at the input end either. I'd check for a "cold" solder joint, or maybe the wire isn't making good contact with the Arduino 5V.

If you can get a clear photo showing the connections, we can take a look.

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1885
 
Posts: 94
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Re: NEO PIXEL WILL NOT LIGHT

Post by 1885 »

When I move the neo stick all the lights come on.
I'm sure I need to work on my soldering.
Attachments
neo2.png
neo2.png (290.3 KiB) Viewed 868 times

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pburgess
 
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Re: NEO PIXEL WILL NOT LIGHT

Post by pburgess »

Yeah, 5V is a cold solder joint...see how it's all balled up? It should flow smoothly between the pin and the copper pad. Cold joints usually happen when you heat up the solder instead of the parts.

Heat up both the pad and pin with the tip of the iron, then try adding just a tiny extra dab of solder.

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1885
 
Posts: 94
Joined: Sun May 24, 2009 2:12 am

Re: NEO PIXEL WILL NOT LIGHT

Post by 1885 »

pburgess wrote:Yeah, 5V is a cold solder joint...see how it's all balled up? It should flow smoothly between the pin and the copper pad. Cold joints usually happen when you heat up the solder instead of the parts.

Heat up both the pad and pin with the tip of the iron, then try adding just a tiny extra dab of solder.
Thanks for the tips. I fixed the cold joint and did a lot better on my next Neo.
It's time to buy a good iron. I do believe that will be less stressful.

https://www.adafruit.com/products/1204

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