Fork me on GitHub

Project Notes

#420 CuttleTalk

Playing audio from a Boldport Cuttle (Arduino) over LiFi with lite2sound

Build

Here’s a quick demo..

clip

NB: or just a short CuttleTalk clip

Notes

Now I’ve built the Boldport lite2sound, time to test it out. I’m inspired by LEAP#417 SimpleSamplePlayer to attempt some LiFi audio transmission by light.

I’m using the Boldport Cuttle (an AVR/Arduino clone) to transmit an audio sample with an LED, and the Boldport lite2sound as a receiver. The audio out from lite2sound is amplified with LEAP#210 TDA7297 Kit

W00t, and it works;-)

Sampling Some Sound

I’ve cheekily snaffled a sample from Boldport’s Intro to the Boldport Variety Show! using node-ytdl and ffmpeg to capture MP3 audio from the video:

ytdl https://youtu.be/VBJBxnPkQbE --filter audioonly -o intro.mp4
ffmpeg -i intro.mp4 -acodec mp3 intro.mp3

I used audacity to clip and clean up a sample, including re-sampling it at 8kHz and exporting as a WAAV file saar_from_boldport.wav.

Finally, I used the sample_encoder.rb Ruby script to convert the WAV file into the sample_saar_from_boldport.h header file which is used by the CuttleTalk.ino sketch loaded on the Cuttle.

ruby sample_encoder.rb sounds/saar_from_boldport.wav > sample_saar_from_boldport.h

Construction

The LiFi broadcast is simply a Cuttle with a high-intensity white LED on pin 11/PB3 and a 220Ω current limiting resistor:

Breadboard

Schematic

Credits and References

About LEAP#420 BoldportAudioLiFi
Project Source on GitHub Project Gallery Return to the LEAP Catalog

This page is a web-friendly rendering of my project notes shared in the LEAP GitHub repository.

LEAP is just my personal collection of projects. Two main themes have emerged in recent years, sometimes combined:

  • electronics - usually involving an Arduino or other microprocessor in one way or another. Some are full-blown projects, while many are trivial breadboard experiments, intended to learn and explore something interesting
  • scale modelling - I caught the bug after deciding to build a Harrier during covid to demonstrate an electronic jet engine simulation. Let the fun begin..
To be honest, I haven't quite figured out if these two interests belong in the same GitHub repo or not. But for now - they are all here!

Projects are often inspired by things found wild on the net, or ideas from the many great electronics and scale modelling podcasts and YouTube channels. Feel free to borrow liberally, and if you spot any issues do let me know (or send a PR!). See the individual projects for credits where due.