AM32 ESC Unlocker

Version 1.0.0 · Bundled bootloaders v17 · 3 May 2026

Unofficial build based on the upstream AM32-unlocker project. Same job: unlock flash‑locked ESCs and install an AM32 bootloader over SWD, without soldering a debug harness.

This variant: refreshed UI (CustomTkinter), macOS (DMG / app) and Windows (exe / portable zip) downloads.

Distribution: only pre-built releases are published here — grab the files from Releases. Source code is not published as part of this distribution.

Why use it

• no permanent SWD solder job
• quick and simple
• same tool covers AM32 MCU targets; bootloaders included
• works with ST‑Link v2, CMSIS‑DAP, J‑Link
• optional custom bootloader

Background

Many ESCs ship with flash locked (often BLHeli_32). To run AM32 you unlock and flash an AM32 bootloader. Prefer buying ESCs that already ship with AM32; this tool is for migrating existing hardware.

Download and run

1. Open Releases and download the build for your OS.
2. macOS: open the DMG, drag the app to Applications. If macOS blocks it on first open, allow it under Settings → Privacy & Security.
3. Windows: run the .exe or unpack the zip. If USB fails, install WinUSB with Zadig.

Official Linux builds (and more docs) live on upstream releases.

In the app, pick the MCU (read the chip if unsure) and signal pin (DShot to the FC — often PA2 or PB4).

Finding the SWD pads

You need exposed SWD pads; if there are none, unlocking may be impossible.

SWDIO vs SWDCLK: if it does not connect, swap the two probe wires — that is normal.

Connecting SWD

Adapters: ST‑Link v2 (clones are fine), CMSIS‑DAP, or J‑Link.

Ground the probe to the ESC. Two dupont leads from SWDIO and SWDCLK; bend the male ends so both tips reach the pads together:

Unlocking

Set MCU and pin, press Start. LED goes red, low beeping while it tries. Power the ESC (no motor). Touch both pins to the SWD pads — tone rises and LED turns orange when the MCU is found; swap wires if needed.

Success: triple beep, “Success!”, LED green. Then use normal AM32 tools to flash firmware.

Troubleshooting

libusb_open() failed with LIBUSB_ERROR_NOT_SUPPORTED on Windows → fix with Zadig.

If something fails, check esc_unlocker.log next to where you ran the app (e.g. AM32 Discord for help).

CAUTION

Wrong lock settings can brick some MCUs irreversibly. Use at your own risk.