# Building and flashing PX4 ## Prerequisites You need a build environment that can build PX4 Autopilot. You can generally use the [same environment as with Apache NuttX](/ucans32k1/apache-nuttx/building-and-flashing-nuttx.md#toolchain), but you will need to install some additional packages. To get started, you can use the [HoverGames virtual machine](https://nxp.gitbook.io/hovergames/developerguide/tools), or install your own Linux (virtual) machine. When you have a basic Linux environment, you only need to [install the PX4 toolchain](https://nxp.gitbook.io/hovergames/developerguide/tools/toolchain-installation) to continue. More information is also available in the [PX4 Developer Guide](https://dev.px4.io/master/en/setup/getting_started.html). If you have not yet cloned the PX4 source code as part of the toolchain installation, you should do so now: ```bash git clone https://github.com/PX4/PX4-Autopilot ``` ## Adding CAN utilities to PX4 If you want to add the `can-utils` apps to PX4 (`candump` and `cansend` applications), you will need to perform an extra step. Here are the steps: 1. From the root of your PX4 directory, run `make nxp_ucans32k146 menuconfig` 2. Navigate to `Application Configuration --->` 3. Navigate to `CAN Utilities --->` 4. Enable all options except `[ ] SocketCAN slcan tool` It should look like this: ![](/files/mS0QNLJH2K8ETplthaoS) Once you've finished this, exit the menuconfig and save, then continue to build PX4 below. ## Building PX4 Autopilot for UCANS32K146 Change your working directory (`cd` command) to the PX4-Autopilot Git repository that you just cloned. Next we will build the bootloader and firmware for our UCAN board. ### Bootloader {% hint style="info" %} You only need to build and flash the bootloader once. If you rebuild/reflash PX4, you can skip all of the bootloader steps. {% endhint %} #### Downloading the Bootloader If you don't want to build the bootloader, you can download it by clicking the file below. {% embed url="" %} UCANS32K146 PX4 Bootloader (Latest build) {% endembed %} Alternatively, run the following command to build the bootloader: ```bash make nxp_ucans32k146_canbootloader ``` The binary file will be located at `PX4-Autopilot/build/nxp_ucans32k146_canbootloader/nxp_ucans32k146.bin`. Keep this file handy for flashing later. ### PX4 Firmware A prebuilt version of PX4 for UCANS32K146 is linked below. This is the latest build of PX4 master. {% embed url="" %} UAVCAN PX4 firmware binary (Latest build) {% endembed %} Alternatively, you can build the firmware by running the following command in the root of the PX4-Autopilot repository: ```bash make nxp_ucans32k146 ``` The .bin file for flashing the firmware will be stored in `build/nxp_ucans32k146_default/deploy`. The file you're looking for is `34.bin`. You can leave the file there or copy it to another location for flashing the board in the next section. ## Flashing PX4 Autopilot to the UCANS32K146 board Download and install the [J-Link Software and Documentation Pack](https://www.segger.com/downloads/jlink#J-LinkSoftwareAndDocumentationPack). It is available for all major operating systems, but we will assume here that you are using a Linux-based OS. Open a terminal and navigate to the directory which holds the `nxp_ucans32k146.bin` file that we build in the previous step. Now start the J-Link tools by entering: ```bash JLinkExe ``` Make sure that the debugger is plugged into both the UCANS32K146 board and your computer. If you are using a virtual machine, the debugger USB device should be made available inside the VM. Also do not forget to power the board. Now enter: ```bash connect ``` You are now asked to specify a device. It is quickest to manually enter the device: ```bash s32k146 ``` The target interface needs to be specified, which is SWD: ```bash s ``` Finally you have to specify the target interface speed. It is recommended to use 1000 kHz: ```bash 1000 ``` Now flash the bootloader with: ```bash loadbin /path/to/nxp_ucans32k146.bin 0x0 ``` The binary will be programmed and this process will also be verified. It should then mention if everything went OK. Next, flash the PX4 firmware binary with: ```bash # If using pre-built binary loadbin /path/to/34-0.1.{commit}.uavcan.bin 0x6000 # If using self-built binary loadbin /path/to/34.bin 0x6000 ``` And you're good to go. You can quit the J-Link tools with: ```bash q ``` You may need to power cycle the device afterwards. The debug console should now be available on LPUART1 (115200 baud) - which is also accessible on the debugger breakout board. ## More information The PX4-build for UCANS32K146 is in an early state and not all features may be available. More information about PX4 Autopilot is available in their [User Guide](http://docs.px4.io/master/en/) and [Developer Guide](https://dev.px4.io/master/en/). Their software development is managed on [GitHub](https://github.com/PX4/PX4-Autopilot). There are also various [support channels](https://dev.px4.io/master/en/contribute/support.html) available. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://nxp.gitbook.io/ucans32k1/px4-autopilot/building-and-flashing-px4.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.