Building the Code
Last updated
Last updated
PX4 can be built on the console or in an IDE, for both simulated and hardware targets.
:::note Before following these instructions you must first install the for your host operating system and target hardware. :::
:::tip For solutions to common build problems see below. :::
The PX4 source code is stored on Github in the repository.
To get the very latest ("main") version onto your computer, enter the following command into a terminal:
:::note This is all you need to do just to build the latest code. If needed you can also . provides a lot more information working with releases and contributing to PX4. :::
First we'll build a simulated target using a console environment. This allows us to validate the system setup before moving on to real hardware and an IDE.
Navigate into the PX4-Autopilot directory and start using the following command:
This will bring up the PX4 console below:
The drone can be flown by typing:
The drone can be landed by typing commander land and the whole simulation can be stopped by doing CTRL+C (or by entering shutdown).
Flying the simulation with the ground control station is closer to the real operation of the vehicle. Click on a location in the map while the vehicle is flying (takeoff flight mode) and enable the slider. This will reposition the vehicle.
:::
To build for NuttX- or Pixhawk- based boards, navigate into the PX4-Autopilot directory and then call make with the build target for your board.
A successful run will end with similar output to:
The first part of the build target px4_fmu-v4 indicates the target flight controller hardware for the firmware. The suffix, in this case _default, indicates a firmware configuration, such as supporting or omitting particular features.
:::note The _default suffix is optional. For example, make px4_fmu-v5 and px4_fmu-v5_default result in the same firmware. :::
Pixhawk 1 with 2 MB flash: make px4_fmu-v3_default
Append upload to the make commands to upload the compiled binary to the autopilot hardware via USB. For example
A successful run will end with this output:
You can also list all configuration targets using the command:
Many build problems are caused by either mismatching submodules or an incompletely cleaned-up build environment. Updating the submodules and doing a distclean can fix these kinds of errors:
The region 'flash' overflowed by XXXX bytes error indicates that the firmware is too large for the target hardware platform. This is common for make px4_fmu-v2_default builds, where the flash size is limited to 1MB.
If building your own branch, it is possibly you have increased the firmware size over the 1MB limit. In this case you will need to remove any drivers/modules that you don't need from the build.
MacOS allows a default maximum of 256 open files in all running processes. The PX4 build system opens a large number of files, so you may exceed this number.
The build toolchain will then report Too many open files for many files, as shown below:
The solution is to increase the maximum allowed number of open files (e.g. to 300). You can do this in the macOS Terminal for each session:
Enter this command:
As of macOS Catalina 10.15.1 there may be problems when trying to build the simulator with cmake. If you have build problems on this platform then try run the following command in your terminal:
Build issues related to arm_none_eabi_gccmay be due to a broken g++ toolchain installation. You can verify that this is the case by checking for missing dependencies using:
Example of bash output with missing dependencies:
"Failed to import" errors when running the make px4_sitl jmavsim command indicates that some Python packages are not installed (where expected).
If you have already installed these dependencies this may be because there is more than one Python version on the computer (e.g. Python 2.7.16 Python 3.8.3), and the module is not present in the version used by the build toolchain.
You should be able to fix this by explicitly installing the dependencies as shown:
The previous sections showed how you can call make to build a number of different targets, start simulators, use IDEs etc. This section shows how make options are constructed and how to find the available choices.
The full syntax to call make with a particular configuration and initialization file is:
VENDOR_MODEL_VARIANT: (also known as CONFIGURATION_TARGET)
VENDOR: The manufacturer of the board: px4, aerotenna, airmind, atlflight, auav, beaglebone, intel, nxp, etc. The vendor name for Pixhawk series boards is px4.
MODEL: The board model "model": sitl, fmu-v2, fmu-v3, fmu-v4, fmu-v5, navio2, etc.
VARIANT: Indicates particular configurations: e.g. bootloader, cyphal, which contain components that are not present in the default configuration. Most commonly this is default, and may be omitted.
:::tip You can get a list of all available CONFIGURATION_TARGET options using the command below:
:::
VIEWER_MODEL_DEBUGGER_WORLD:
VIEWER: This is the simulator ("viewer") to launch and connect: gz, gazebo, jmavsim, none
:::tip none can be used if you want to launch PX4 and wait for a simulator (jmavsim, Gazebo, Gazebo Classic, or some other simulator). For example, make px4_sitl none_iris launches PX4 without a simulator (but with the iris airframe). :::
:::tip You can get a list of all available VIEWER_MODEL_DEBUGGER_WORLD options using the command below:
:::
Notes:
Most of the values in the CONFIGURATION_TARGET and VIEWER_MODEL_DEBUGGER have defaults, and are hence optional. For example, gazebo-classic is equivalent to gazebo-classic_iris or gazebo-classic_iris_none.
You can use three underscores if you want to specify a default value between two other settings. For example, gazebo-classic___gdb is equivalent to gazebo-classic_iris_gdb.
You can use a none value for VIEWER_MODEL_DEBUGGER to start PX4 and wait for a simulator. For example start PX4 using make px4_sitl_default none and jMAVSim using ./Tools/simulation/jmavsim/jmavsim_run.sh -l.
Additional make targets are discussed in relevant sections:
...
These are extracted at build time from the active git tag for your repo tree. The git tag should be formatted as <PX4-version>-<vendor-version> (e.g. the tag in the image above was set to v1.8.1-2.22.1).
:::warning If you use a different git tag format, versions information may not be displayed properly. :::
:::note You may need to start QGroundControl before proceeding, as the default PX4 configuration requires a ground control connection before takeoff. This can be . :::
:::tip PX4 can be used with a number of other , including , and . These are also started with make - e.g.
For example, to build for hardware you could use the following command:
The following list shows the build commands for the boards:
: make px4_fmu-v6x_default
: make px4_fmu-v6c_default
: make px4_fmu-v6c_default
: make px4_fmu-v6c_default
: make px4_fmu-v5x_default
: make px4_fmu-v5_default
: make px4_fmu-v5_default
: make px4_fmu-v5_default
: make px4_fmu-v5_default
: make px4_fmu-v4_default
: make px4_fmu-v4pro_default
: make px4_fmu-v3_default
: make px4_fmu-v3_default
: make px4_fmu-v3_default (supports 2MB Flash)
: make px4_fmu-v2_default
: make px4_fmu-v2_default
: make px4_fmu-v2_default
: make px4_fmu-v2_default
:::warning You must use a supported version of GCC to build this board (e.g. the same as used by ) or remove modules from the build. Building with an unsupported GCC may fail, as PX4 is close to the board's 1MB flash limit. :::
Build commands for non-Pixhawk NuttX fight controllers (and for all other-boards) are provided in the documentation for the individual .
Build commands for other boards are given the (usually under a heading Building Firmware).
is the officially supported (and recommended) IDE for PX4 development. It is easy to set up and can be used to compile PX4 for both simulation and hardware environments.
If you're building the vanilla master branch, the most likely cause is using an unsupported version of GCC. In this case, install the version specified in the instructions.
Run this script , or
This can be resolved by removing and .
See .
MODEL: The vehicle model to use (e.g. iris (default), rover, tailsitter, etc), which will be loaded by the simulator. The environment variable PX4_SIM_MODEL will be set to the selected model, which is then used in the to select appropriate parameters.
DEBUGGER: Debugger to use: none (default), ide, gdb, lldb, ddd, valgrind, callgrind. For more information see .
WORLD: (Gazebo Classic only). Set the world () that is loaded. Default is . For more information see .
The VENDOR_MODEL_VARIANT options map to particular px4board configuration files in the PX4 source tree under the directory. Specifically VENDOR_MODEL_VARIANT maps to a configuration file boards/VENDOR/MODEL/VARIANT.px4board (e.g. px4_fmu-v5_default corresponds to ).
bloaty_compare_master:
The PX4 Firmware Version and Custom Firmware Version are published using the MAVLink message, and displayed in the QGroundControl Setup > Summary airframe panel:
