Reverse engineering the PixMob concert light bands
PixMob concert bracelets have RGB LEDs that synchronize across thousands of people in a stadium show. Not just color syncing, but detailed patterns such as the heart in the photo are possible. Cra0 tore one apart to see how it works, and dumped the EEPROM with a Dangerous Prototypes Bus Pirate.
The wristbands seemed simple at first: a pair of coin cell batteries, two LEDs, and an inert white plastic cover that had the word “PIXMOB” marked at the bottom. But as the concert began, they transformed into a stunning display of light, perfectly synchronized across thousands of people around the arena. My curiosity was sparked; what was the secret behind controlling these devices?
I hid my wristband under my seat. It didn’t light up with the others, which was my first clue. That’s when it hit me—the wristbands weren’t using RF; they were controlled by infrared signals. This realization set me off on a journey to explore the tech behind these devices.
Read more about reverse engineering these devices in Part 1 and GitHub. Via Dangerous Prototypes on X.
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