How many Neopixels can a Gemma support

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leafOnTheWind
 
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How many Neopixels can a Gemma support

Post by leafOnTheWind »

Hi, I am getting LED's for a project of mine and I was wondering how many NeoPixels a single Gemma can support. From the "Gemma-Powered NeoPixel LED Sound Reactive Drums" guid, it seems as if a single Gemma can support at least a metre of whatever density NeoPixel strip is being used but at the same time, the product description says to be mindful of the memory allocation for how many NeoPixels are being used. My hope is that a single Gemma could support 2 metres of the lowest density NeoPixels. Thanks!

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Franklin97355
 
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Re: How many Neopixels can a Gemma support

Post by Franklin97355 »

2 metres of the lowest density NeoPixels.
do you mean 60 pixels?

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leafOnTheWind
 
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Re: How many Neopixels can a Gemma support

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Franklin97355
 
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Re: How many Neopixels can a Gemma support

Post by Franklin97355 »

You would want to power the strip directly from 5 volts but for the controls the Gemma should be able to handle it.

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Disciple
 
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Re: How many Neopixels can a Gemma support

Post by Disciple »

I tested a Trinket 5V with a random color wave sketch up to the nearest dozen, and it controlled 108 pixels no problem. Not a Gemma, but close enough? Plenty of available current was a definite must.

@Engineer: Wouldn't 3V or 3.7V power for the NeoPixels be a better match for Gemma's logic?

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Disciple

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