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OpenFC, Betaflight. Step 1 of 4

Put your OpenFC in bootloader mode

On an OpenFC-Lite (OpenFC-Lite only), clicking Update firmware on the firmware page restarts the board into bootloader mode for you, so usually you can skip this page. Use it when that step fails, for the Lite Mini, or for the copy method.

In bootloader mode the board shows up as a drive called RP2350. The bootloader is in ROM inside the chip and cannot be erased.

You need

  • A computer running Windows, macOS or Linux
  • A USB-C cable that carries data (some cables only charge)
  • Your OpenFC-Lite or OpenFC-Lite Mini

Steps

  1. Make the drone safe. Take the propellers off and unplug the flight battery. Only the USB cable will be connected from now on.

    You should see: No battery connected and no propellers on the motors.

  2. Save your settings (skip this on a brand-new board). If you have already set the board up, open the Betaflight app in Chrome or Edge, plug in USB and click Connect. Open the CLI tab, type diff all and press Enter. Click Save to File and keep the file somewhere safe. Then click Disconnect.

    You should see: A text file with your settings in your downloads folder.

  3. Unplug the USB cable. Unplug the cable from the flight controller. Leave the other end in the computer.
  4. Find the BOOT button. The board has a small push button for bootloader mode, usually labelled BOOT or BOOTSEL. Its position differs between the OpenFC-Lite and the Mini, so look at the label printed on your board and at the board's documentation: OpenFC-Lite on GitHub or OpenFC-Lite Mini on GitHub.

    You should see: You know which button to press. If you cannot find it, use the CLI method under "Other ways in" below.

  5. Hold BOOT and plug in USB. Press and hold the BOOT button, plug the USB cable into the board while you keep holding it, then let go after about a second.

    You should see: A new drive called RP2350 appears on your computer. It contains two files, INDEX.HTM and INFO_UF2.TXT. The board is now in bootloader mode.

Other ways in

If the board runs Betaflight, type bl rom in the Betaflight app's CLI tab and press Enter. That is what the firmware page does for you. If no RP2350 drive appears, use the BOOT button.

If it doesn't work

No RP2350 drive appears.
Try another USB cable first: many cables only charge and carry no data. Plug straight into the computer, not through a hub or dock, and try another port. Make sure you hold the button down before the cable goes in.
The board shows up as a serial port or connects in the Betaflight app instead.
It started normally, so the button was not held while the cable went in. Unplug, hold BOOT first, then plug in.
I am not sure the drive is the flight controller.
Open INFO_UF2.TXT on the drive. It should say Board-ID: RP2350. If it says anything else, do not copy firmware onto it.
Nothing happens on any cable, port or computer.
Open a support ticket and tell us what you tried. Do not try to fix the board with a soldering iron.

Go to the firmware page