Cannot change colors on NeoPixel strip

Using Arduino LEDs and Multiplexing
1

I have tried and read a lot of stuff on my issue which is basically no matter what sketch i upload to an Arduino UNO, the lights on my strip do not change. I have tried just USB power and a 5-v, 3-amp DC power supply. I've attached an image of the circuit using the 5-v power supply.

I run the Blink program to verify sketches are being uploaded and it works.

Here is the simple sketch i last tried. The way I understand this sketch, all the lights should be off but see attached image.

It may be difficult to see but I have connected the grounds from the strip and the power supply to the Arduino.

Thanks for any help.

#include <Adafruit_NeoPixel.h>
#define LED_COUNT 14
#define LED_PIN 6
Adafruit_NeoPixel strip(LED_COUNT, LED_PIN, NEO_GRB + NEO_KHZ800);

void setup() {
// put your setup code here, to run once:
strip.begin();
strip.show();
}

void loop() {
// put your main code here, to run repeatedly:

}

2

Where's the image?

3

Here is the simple sketch i last tried.

Well in that code you never actually tell the strip to display anything so there is little wonder why you are seeing nothing.

What happens when you run the examples that come with the Adafruit library?
Do you know how to find them? Use the menu File-> Examples scroll down and find the library then across to examples and finally choose your example. Then if it needs modifying like changing the number of LEDs then use the Save As in the file menu to make an editable copy in your own storage space.

4

I could not get the image to upload. I tried the recommended format of jpeg but got an error message.

As to the query about the code, I purposely tried to run that code to turn off all the light. It did not do that. When I plug in the USB cable, lights on the strip come on - not all of the them, but some. When I run the script, the lights do not turn off ad I expected them to.

5

So have you tried the examples that came with the library?

6

Yes. I've tried a few of them like strandtest and others.

7

And?

If you are saying that these don’t work then you have something wrong with your physical setup.
Something like :-
The wires are not making proper connections or,
you have some thing the wrong way round or,
Your power supply has insufficient current capability or,
Your Arduino is broken or,
Your LED strip is broken or,
You are using the wrong circuit.

So if you need help you have to engage with us, say what example you are using, what LEDs you have and a link to where you bought them, what schematic you have and photographs of your setup showing clearly where all the wires go.

8

Grumpy_Mike:
and photographs of your setup showing clearly where all the wires go.

Taken perfectly focused in outside full daylight but not direct sun, not in a dark room. :astonished:

9

Thanks to all. I tired one suggestion suggesting the strip may be broken. I must have done something to the strip because I got another one and the circuit I've been using works with it. The old strip lights up some pixels but none of the sketches change the pixels.

10