ECE434 Project-Infinity Mirror

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thumb‎ Embedded Linux Class by Mark A. Yoder

Team members: Tyler Thenell, Aidan Moss

Grading Template

I'm using the following template to grade. Each slot is 10 points. 0 = Missing, 5=OK, 10=Wow!

09 Executive Summary
09 Packaging
09 Installation Instructions 
09 User Instructions
09 Highlights
09 Theory of Operation
09 Work Breakdown
09 Future Work/Conclusions
09 Demo/Poster
00 Not Late

Score:  90/100

Executive Summary

Our ECE 434 we are using the Beagle Bone we are writing audio controlled python code that can then change the brightness and color of a LED strip to change in sync with music. The LEDs are encased in a decahedron of acrylic that has been treated with a one way mirror film to create an optical illusion that makes it appear the lights are going on forever. This control is achieved by using a kernel driver that communicates with the Beagle Bones PRU to relay data to the LEDs. Example picture of what the completed system looks like:



·Acrylic sheets

·Strip of SK6812 LEDS

·Adhesive (we used hot glue)

·KY037 Microphone

·One way mirror film




Installation Instructions

Clone repo located here: →

This repo contains all the code needed to run the SK6812 LED strands to begin running the PRU driver simply:

·cd down into InfMirror/LEDStatic/

·run $source

·run $make

The kernel driver should be active, to test you can run commands in which will turn the first LED in your strip white if it is running correctly if not follow the commands in section 1.16 of the link below as you may not have the driver installed that the kernel driver requires:

Physical Pinout:

·P9_29 → LED Strip data line

·P9_40 → Microphone Digital Output

User Instructions

·After restart, start the PRU driver using the installation instructions used above.

·Run any python file using $./

· and are the python files with integrated support for microphone input

·Interact with the driver and change induvial lights using the commands explained below

Driver Commands Explained

Set up the data you want to send using the command below, replace values in quotes with desired values:

·$ echo "Led position in strip" "Red led" "Green led" "Blue led" "White led" > /dev/rpmsg_pru30

Send the data to the strip:

·$ echo -1 > /dev/rpmsg_pru30



Demo video:

Theory of Operation

The software for this project uses a kernel driver that is coded in C to talk directly with the PRU that then relays info to the SK6812 LED strip that uses RGBW LEDs. Using this driver there is then python programs that can be written to communicate with driver. This is super nice because it allows the software and coding of new light shows to be easy using a high level language but also we maintain a lot of the advantages of using something that's low level like C.

Work Breakdown

Both members helped on both sections but each member researched and was a expert on their specific part.


Hardware assembly 


LED library integration

Future Work

·Startup driver on boot sequence

·Add Blynk integration so you can control what sequence you are running from a smart phone

·Refine the beat detection and add a more sensitive microphone input


Fun project that we will be using later on as a cool decoration item to use in our rooms. Has its own unique challenges but its also very expandable as you could add control from your phone, or a microphone input or sever different types of light shows.

thumb‎ Embedded Linux Class by Mark A. Yoder