Aaron Christophel tore down a €15 UGreen 240W USB-C cable with an integrated LCD and found an EN32LF056 MCU confirmed via SWD as a Cortex-M0+ with 64 kB of Flash and 4 kB of SRAM, driving a small IPS display over a flat flex cable connector, with supporting voltage regulators and a MOSFET for the backlight.
Getting inside requires knowing where to apply pressure on the display cover first, then ditching subtlety and using side-cutters on the aluminium shell. The MCU has no USB interface access, it only reads voltage and current, but the SWD pads sit underneath the display and are reachable without destroying the unit.
Christophel already reflashed the firmware to play video frames. The full teardown video is worth watching for the disassembly sequence alone, specifically the non-obvious order of operations that avoids permanently damaging the connector, which is the detail that makes custom firmware on these actually repeatable.
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