Building and Flashing the Firmware

This guide assumes you are running Ubuntu 22.04 LTS, which is the currently supported development environment.

Installing the ARM Embedded Toolchain

sudo apt install gcc-arm-none-eabi

You can test the installation and check which version is installed by running arm-none-eabi-gcc --version.

Building the Firmware from Source

1. To build the firmware, first clone the firmware repository:

   git clone --recursive https://github.com/rosflight/rosflight_firmware
   

2. Create build directory:

   cd rosflight_firmware && mkdir build && cd build
   

3. Build using: (board_name should be either varmint or pixracer_pro)

   cmake .. -DBOARD_TO_BUILD=<board_name> && make -j
   

Flashing firmware

Install STM32CubeProgrammer

We use the STM32CubeProgrammer to flash the flight controller.

1. Download the programmer here. You may have to enter your email to download the software.
2. Install the software by following the instructions in the downloaded package.

Flashing the Varmint

Needed tools

You will need an ST-Link STM programmer to flash the firmware. We use ST-Link V2, and you can find it on Mouser.

1. Plug the end of the ribbon cable into the 6-pin slot on the Varmint. You may have to make your own cable that connects the ST-Link to the 6-pin connector.

   Danger

   The Varmint has 2 6-pin connectors. Do not connect the ribbon cable to the port closest to the power wires.

   

2. Power on the Varmint by connecting a battery to the board.

3. Open STM32CubeProgrammer.

4. Plug in the USB connector from the ST-Link to the computer. Select "Connect" in the STM32CubeProgrammer. This should detect the ST-Link and connect automatically.

5. Navigate to the programming page.

6. Select the hex file that was just built and click "Open".

   /path/to/rosflight_firmware/build/boards/varmint_h7/varmint_10X/varmint10X.hex
   

   

7. Select the appropriate options and press "Start Programming"

Flashing the Pixracer Pro

Flashing the Pixracer Pro is a very similar process to flashing the Varmint.

1. The Pixracer Pro does not use the same 6-pin connector to connect to the ST-Link. Instead, it uses a TC2030 connector with retaining clips.

   Connectors we use

   In addition to the ST-Link V2 board linked above, we use these cables to flash the Pixracer Pro:

   1. 20-pin ribbon adapter board (connect the ST-Link to this adapter)
   2. Programming cable that connects to the adapter board
   3. TC2030 clip to attach the programming cable to the board

   

2. Power on the Pixracer Pro using a USB-C port.

3. Follow the instructions from the Varmint flashing guide.