LEDs, Microcontrollers, and Microphones - The World’s Most Complicated Backsplash?

Join me as I discuss my latest project - building a glass tile backsplash with individual LEDs on each tile. I'll also be adding touch sensors to each tile to implement touch feedback, using a distributed processing technique, and leveraging the existing LED communication protocol. We'll cover electronics design, LED protocols, PCB fabrication, soldering, and... home improvement?
To do this, I'll be using a distributed network of microcontrollers, around 160 microcontrollers. Each microcontroller will read the values from two microphones (320 total!), perform computations, and send the data to the main controller so that the LEDs can be controlled in unique ways based on touch feedback. Since this is a DIY project with limited funding, it was necessary to use one of the cheapest microcontrollers available, the Puya PY32. I'll discuss some of the benefits and challenges of these devices.
I'll also cover design and construction of the prototype board, including the electronic CAD schematic, circuit board layout, surface mount (SMD) soldering, and more.
This is part of a larger series covering the build, so be sure to like and subscribe to get all the updates!
00:00 Introduction
00:34 The Concept
02:00 Overall Implementation
04:09 Drawing out the Implementation
05:03 How the Neopixels Work
08:35 How to Listen to 320+ Microphones
10:29 Microcontroller Selection
12:02 Hardware Selection
13:47 PCB Selection
15:19 Other Technical Detail
16:30 KiCAD Schematic and Layout
19:28 A Brief Discussion of Software and the Puya PY32
24:02 Making a Solder Paste Stencil
25:08 Assembling the Prototype
26:42 Conclusion

[@tsmwebb]

That was impressive. Thanks for sharing. Hail to the Ineffable Algorithm for suggesting your video!

[@lenaschimmel]

Hey, great project and a very nice video! The quality is like on the big and famous channels, so I was surprised to see that your's not (yet) that famous :)
Regarding the production of the final flex PCBs that you mention at the end... are you sure you want to do this manually? If you get your parts from LCSC anyway, it should be easy and affordable to let it be assembled by JLCPCB.

[@AllTradesZach]

Thanks for the encouragement!
I should really consider having someone populate them, but at this point I might be trapped in a sunk cost fallacy, since I've already bought the parts and am making tooling to populate the boards.

[@lenaschimmel]

@@AllTradesZach Oh, I can understand this. I've had different variations of that fallacy in my hardware projects as well. Anyway, if populating them yourself becomes too tedious at some point, some companies can assemble parts that you send them. (I think JLCPCB only accepts shipments from China for this, but PCBWAY could work.)

[@lohikarhu734]

Lp55321...3 RGB, or 9 individual, LEDs...I2C, plus they have a trigger input to execute one of 3 "programs", without requiring MCU activity, after the program is loaded ... Nokia used a similar driver to get ripple effects, breathing, blinking...
There's a really nice driver in Rust, and more in Arduino, as well as a general driver in Linux

[@AllTradesZach]

That's an interesting part! A little pricey, but I'm going to keep that in mind for a couple other projects I'm working on.