A Stranger Things Light Wall Lets a Phone Fix the Letter Wiring
The Halloween decoration keeps its settings through a power cut and even has a Knight Rider mode for checking the lights.
The forgiving feature in this Stranger Things wall is the one you need after hanging the alphabet in the wrong order. A letter can move in software while the soldering iron stays cold. Finally, some character development that doesn’t require rewiring.
MyEmbeddedStuff built the decoration with his daughter for Halloween, taking inspiration from a message-flashing street display in Madrid. Ordinary string lights supplied the bulb shells and wires. He replaced their regular LEDs with two addressable ones per letter, making 52 lights across the alphabet. The letters themselves are EVA foam, hung with transparent fishing line.
A Seeed Studio XIAO ESP32-S3 runs the display. The WS2812B LED strip gets cut into pieces for the bulbs; the LEDs pass data along the chain, avoiding a separate control wire for every letter. The maker includes a schematic and puts a 470-ohm resistor near the first LED to reduce signal trouble.
The project repository supplies the firmware and identifies the data connection as A0, GPIO1. It supports up to 100 LEDs, numbered from zero to 99 in the settings. That is useful headroom for someone adapting the display, although an extra-long strand still needs its own power planning. The published one-letter-at-a-time animation is a different load from lighting a larger display all at once.
The board creates a Wi-Fi network called XIAO-LED-Control. Once connected, a phone opens 192.168.4.1 to reach the controls. The browser is talking to the decoration itself, with no internet connection required. An alphabet wall already has enough supernatural dependencies without adding a cloud account.
The README puts letter assignments, colors and timing in a Settings tab, with changes kept after a reboot. Those are three different ways a finished display can go wrong: the wrong lamp, the wrong appearance or a message too fast to read. Having them together makes tuning possible from where the audience stands, rather than from behind the wires.
The maker also includes a Knight Rider effect, which helped check the lights during assembly. In message mode, random letters can flicker before a dark pause and the actual text. An adjustable gap lets two consecutive copies of a letter read as two flashes; otherwise, the wall can technically spell correctly while its audience misses a character.
That distinction gives this build a useful second life beyond Halloween. A message display needs people to recognize the sequence, and editable timing keeps the human part of the connection adjustable. The gap between flashes is what lets the audience distinguish a repeated letter from one that simply stays lit longer.
No soldering sequel required.