Going from the Arduino to ESP32
The animations are essentially large 2D arrays of CRGB data, and even 1 animation of 5 frames was too large for the Arduino UNO (SRAM 2KB) so I switched to the ESP32 C6 Mini (SRAM 512 KB) – plenty of space for some small animations.
I used the Arduino IDE – I downloaded the ESP32 Espressif board manager. The only issue was that serial commands (e.g. serial.print, serial.begin etc.) would not show up in my Serial Monitor – which made debugging efforts super frustrating. To fix this issue: Tools > USB CDC On Boot > Enabled.
Schematic
Here’s my ‘schematic’. I also added a light dependent resistor in series with a 5k resistor to make a voltage divider. By detecting the voltage (aka brightness), I could use this to detect when the pop up was closed which then turned off the screen (using FastLed.clear). I added a LED to turn on when a button was pressed to give the illusion of a real remote.
Testing that the LDR works…
Constructing the Pop Up
Pop up parts ready to cut out.
I added a layer of diffusion paper to diffuse the light from the LEDs and some double sided foam to prevent the light of the LEDs spilling out around the edges of the screen.
Testing the LED screen.
The Remote
The ‘remote’ has quite a lot of components – buttons, LDR, resistors etc. I decided to use copper tape to make some of the connections. I first made a test circuit to see if I could solder to the tape – it was incredibly easy (obviously!).
Here’s the remote part of my pop up all wired up.
I put dupont connectors on the end of the wires – a bit of a finicky process but with enough practice turned out to be fairly easy. I liked that I could ‘group’ wires into the same plastic housing- you can see I’ve done this for the 4 buttons – I did change some of the button pins on the esp32 so that they all connected ‘in a row’.
My finished TV Pop Up
And here’s my final TV Pop Up!
Conclusions
I think my popup looked great – I was honestly surprised that my homemade LED matrix worked! I think the only issue was the mess of wires coming out of the popup. Next time, I’d make a PCB and integrate the ESP32 into the popup itself.
I’d like a denser LED Screen- maybe using SK6805 EC10? The screen would have to be a PCB as well as those LEDs are SMD.
There’s some light spillage at the bottom of the TV because there wasn’t enough space to put some double sided tape – so some more tweaking of the pop up design is required.
A way to funnel the light of the individual pixels more? Light barriers in between the pixels themselves.
I’d like to make longer animations or convert short videos- with my code as it is, it might eat up a lot of SRAM. Consider other options for making the animations e.g. https://sourceforge.net/projects/led-matrix-studio/ Or figure out how to store the animations in flash memory (there’s 4MB on the ESP32-C6) and call them.
Audio – I haven’t explored audio in any of my projects yet and this is a perfect one to do so. Add a speaker to my TV.