NeoPixel issue

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JKBear331
 
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NeoPixel issue

Post by JKBear331 »

So I'm working on a project for a theater class I'm taking and I am using a metro to control a 5m strip of neopixels and I am having a weird issue of them flashing and not being the color that they are supposed to be or them being very choppy when doing a run pattern or such. Any ideas? Don't think it is the power supply as that is 5v 20a and it should only be 2a per meter.

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adafruit_support_bill
 
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Re: NeoPixel issue

Post by adafruit_support_bill »

How do you have them wired? With 5 meters, you should be feeding power directly to the strip at both beginning and end at least.

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JKBear331
 
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Re: NeoPixel issue

Post by JKBear331 »

Only power on one end. I thought as they were diodes that you could only put power on the input end(probably something I learned at robotics it think). do you think that that would fix it

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Re: NeoPixel issue

Post by adafruit_support_bill »

You are not powering the diodes directly. Each pixel chip has a built-in driver that takes its power from the +5v and GND bus traces that run the length of the strip. If you only feed power from one end of a long strip, the voltage drop at the far end can cause the pixels to misbehave.

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JKBear331
 
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Re: NeoPixel issue

Post by JKBear331 »

ok I can try that. Any other ideas incase that isn't the issue?

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Re: NeoPixel issue

Post by adafruit_support_bill »

Make sure that you have a good ground connection between the Metro and the input end of the strip.

If you are using the same power supply for both the Metro and the strip, run power directly to the strip first. Then run power and ground from the input end of the strip back to the Metro.

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