If BMCU Flasher or my other open-source projects are useful to you and you would like to support further development:

 

Cross-platform flasher for BMCU (WCH ISP protocol).

• OS: Linux / Windows / macOS / Android
• Modes:
  • USB (BMCU with CH340 on board, AutoDI)
  • Native USB (Toaiot BMCU built-in USB, no CH340)
  • TTL (pin header / external USB-Serial, manual BOOT entry)
• Android:
  • USB (CH340 + USB OTG)
  • Native USB (Toaiot built-in USB + USB OTG)
  • TTL (external USB-Serial, manual BOOT entry)
  • Online Bambu / Klipper firmware selection
  • Local .bin file flashing
  • App language follows system language

Download

Download prebuilt binaries from Releases.

Main builds:

• Windows x64: BMCU-Flasher-windows-x64.zip
• Windows x86: BMCU-Flasher-windows-x86.zip
• macOS Apple Silicon (arm64): BMCU-Flasher-macos-arm64.zip
• macOS Intel (x86_64): BMCU-Flasher-macos-x86_64.zip
• Linux x64: BMCU-Flasher-linux-x64.tar.gz
• Linux arm64: BMCU-Flasher-linux-arm64.tar.gz
• Android APK: BMCU-Flasher-android.apk

Legacy / experimental / community (older OS, best-effort):

• Windows legacy (older Windows): BMCU-Flasher-windows-legacy-x64.zip, BMCU-Flasher-windows-legacy-x86.zip
• macOS Catalina 10.15 (Intel): BMCU-Flasher-catalina-1.2.1.zip (community build by Doyle4, tested on Catalina)
• macOS legacy try (CI attempt): BMCU-Flasher-macos-x86_64-legacy-try.zip (may not run on Catalina)

Run from source

Install the Python dependencies:

python -m pip install -r requirements.txt

Then start the GUI:

python bmcu_flasher_gui.py

On some Linux distributions, Tkinter may need to be installed separately (for example python3-tk on Debian/Ubuntu).

Android requirements

• Android 5.0+ (API 21+) (minSdk=21)
• USB OTG + USB host mode
• CH340 supported for USB mode
• Toaiot Native USB supported through the CH32V203 USB ISP bootloader
• External USB-Serial adapters supported for TTL mode
• TTL automatically retries the full flash at 115200 baud if the fast transfer fails
• Do NOT plug USB or flash while BMCU is connected to the printer

Firmware

Latest firmware:

• Bambu: https://github.com/jarczakpawel/BMCU-C-PJARCZAK
• Klipper: https://github.com/jarczakpawel/BMCU-Klipper

GUI has "Online" firmware selection:

• choose Bambu or Klipper
• Bambu: choose mode, AMS_AUTO (recommended) / legacy AMS_A-D, retract length, AUTOLOAD and RGB
• Klipper: the latest single firmware.bin is downloaded automatically
• both desktop and Android can also flash a local .bin file

Drivers (CH340)

In USB mode (CH340), drivers may be required on Windows. Linux and macOS usually work out-of-the-box.

TTL bootloader entry

For the initial TTL bootloader entry:

• Disconnect the USB cable from the USB-Serial adapter/BMCU.
• Hold the BOOT button.
• While holding BOOT, connect the USB cable.
• Release BOOT only when the LED on the BMCU main board lights up.

If the flasher later asks you to re-enter the bootloader during the same flash:

• Keep USB connected.
• Hold BOOT.
• Tap RESET once.
• Release BOOT.

TTL is wired as RX/TX crossed, 3V3 to 3V3 and GND to GND. Do not connect 24V while flashing through the TTL adapter.

Usage

GUI (recommended):

• Run the app
• Click "Online" to pick the exact firmware variant (mode / slot / retract / autoload / RGB)
• Click "Help" inside the app (wiring + bootloader steps)

Android:

• Install APK
• Choose USB, Native USB or TTL mode
• Choose Online or a local .bin file
• Online: choose Bambu or Klipper
• Click "Flash"

CLI (optional):

• USB (auto port by VID/PID):

python3 bmcu_flasher.py firmware.bin --mode usb

• TTL (manual bootloader entry, port required):

  python3 bmcu_flasher.py firmware.bin --mode ttl --port /dev/ttyUSB0

• Native USB (Toaiot built-in USB, no serial port):

  python3 bmcu_flasher.py firmware.bin --mode native_usb

Credits

Native USB support is based on the implementation and hardware testing from the Toaiot BMCU-Flasher fork.

License

MIT - see LICENSE.