Controlling LEDs with LDR measurements - which controller to

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3426543
 
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Controlling LEDs with LDR measurements - which controller to

Post by 3426543 »

Hi,

I'm working on a project where I plan to combine multiple Neopixel strips and a large grid of LDRs - I hope you can give me some advice.
What I am trying to do is to get individual segments of the strips to (simultaneously) respond to measurements of one of the LDRs.
I've been doing tests with an Arduino redboard, one LED strip (divided in the code in 4 segments) and 4 LDRs - so far so good.

My question is: what would be the best way to scale up? Ideally I would want to use up to 30 LDRs which would each control segments of about 16 LEDs (480 LEDs in total = 16 30LED/m strips).

I've been looking at the Arduino Mega, the Teensy 3.1 and the Fadecandy in combination with an Arduino (to read the LDR data). From what I've read each of these should be able to support the number of LEDs I would be driving. But what would be the fastest and easiest way (I am a total beginner) to collect the LDR data and send it to the LEDs? If I use one analogue input for each of the LDRs I would already need 30 inputs so I assume I would need two boards, whichever I use. Or not?

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adafruit_support_mike
 
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Re: Controlling LEDs with LDR measurements - which controlle

Post by adafruit_support_mike »

The core principle of scaleable design is "divide and conquer".

However big your system will be, start by asking, "how can I split this into two identical pieces?" If you can make that happen, you get half your design for free. Then look at the half you still need to design and ask, "is this simple enough to build and maintain as a single unit?" If so, build it. If not, ask, "how can I split this into two identical pieces?" again.

Keep splitting and examining until you have a unit you're willing to build, test, and maintain. Once you have that working, build another one and get the two running in parallel. Then build two more and put those in parallel with the first pair. Push all your design and integration challenges as far down the scale as you can, then learn everything you can from the smaller assemblies as you build your way up to the final product.

As you work your way up the construction stack, you may find ways to make your basic design unit larger. Instead of building four identical modules, you may find it's easier and more efficient to build a single module that does the same job as four independent units. That decision will be driven by your experience building and connecting working devices though, so you'll be able to make your decision based on production data rather than design estimates.

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