---
title: On-chip debugging
page_id: openocd_gdb_debugging
---
One of the key components of getting really serious about developing on
the crazyflie, is to dive into the C-based firmware. If you really want
to do some major changes to the intrinsic of the code, it is essential
to have proper tools to be able to debug the code (place breakpoints,
read real-time values ect\...). On this page, we will put a few examples
how to do this with IDE\'s and different environments.
> **_NOTE:_**
> This page requires our debug adapter and ST Link V2 Debugger! See
> this page: [Debug adapter](https://wiki.bitcraze.io/projects:crazyflie2:debugadapter:index)
## Debugging using VS Code
Thanks to the [Cortex-Debug](https://marketplace.visualstudio.com/items?itemName=marus25.cortex-debug) extension, it is now easily possible to debug ARM executables straight inside of VS Code!
### Mac OS and Ubuntu
#### Prerequisites
First ensure that you have the ARM GCC toolchain and OpenOCD installed and in your path. To check, run:
which openocd
which arm-none-eabi-gcc
The path to your OpenOCD binary and ARM GCC binary should output. If not, try installing them again.
##### Ubuntu
These steps have been tested on Ubuntu 20.04. The link to gdb-multiarch is required because Ubuntu does not ship arm-none-eabi-gdb anymore, but the new gdb-multiarch that supports all architecture.
sudo apt-get install openocd
sudo apt-get install gcc-arm-none-eabi gdb-multiarch
sudo ln -s /usr/bin/gdb-multiarch /usr/local/bin/arm-none-eabi-gdb
If you do not have vscode yet, the easiest way to install it on Ubuntu is via snap using 'Ubuntu Software' of by typing:
sudo snap install --classic code
##### Mac OS
brew install open-ocd
brew tap PX4/homebrew-px
brew install arm-none-eabi-gcc
### The Cortex Debug Extension
Install the [extension](https://marketplace.visualstudio.com/items?itemName=marus25.cortex-debug) either by clicking "Install" on the web page, or by searching "Cortex Debug" in the Extensions tab of VS Code.
Click on "Run", then "Add Configuration", then "Cortex Debug".
This should automatically create the needed "launch.json" file.
### Configuring Cortex Debug
Inside of the file, replace everything with the following:
{
// Use IntelliSense to learn about possible attributes.
// Hover to view descriptions of existing attributes.
// For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
"version": "0.2.0",
"configurations": [
{
"name": "Cortex Debug",
"cwd": "${workspaceRoot}",
"executable": "./cf2.elf",
"request": "launch",
"type": "cortex-debug",
"device": "STM32F405",
"svdFile": "STM32F405.svd",
"servertype": "openocd",
"configFiles": ["interface/stlink-v2.cfg", "target/stm32f4x.cfg"],
"runToMain": true,
"preLaunchCommands": [
"set mem inaccessible-by-default off",
"enable breakpoint",
"monitor reset"
]
}
]
}
### Explaining the Cortex Debug configuration
- "svdFile" refers to the necessary file for peripheral registers to show up nicely in the debug pane, all named and structured; we'll add it in the next step
- "configFiles" refers to the files you need so that OpenOCD knows what device and interface you're using; it should already come with them
- "runToMain" tells the GDB debug server to jump to main by default
- "preLaunchCommands" specifies the commands for the GDB server to send before giving away control to you; the commands here mimic the options that the above tutorial for Eclipse specifies
### Installing the SVD file
Now for the SVD file: just download it from [here](https://raw.githubusercontent.com/posborne/cmsis-svd/master/data/STMicro/STM32F405.svd) and into your root directory. Make sure it has the exact name of "STM32F405.svd"!
### Debugging!
After all this, go to the Debug tab of VS Code (on the left sidebar, the icon with the little bug next to the play button), and hit that play button next to "Run"!
If you followed everything, it should start running nicely and look a little something like this:
Notice the nice peripherals pane at the bottom, along with the variables pane at the top. Awesome, now you can code _and_ debug all within VS Code!
---
## Debugging using eclipse
### Ubuntu
> **_Versions:_**
>
> - Ubuntu 18.04.2 LTS (64 bit)
> - Eclipse 2019-03 (Eclipse IDE for C/C++ Developers)
#### Installing prerequisites
First install GDB and openOCD:
sudo apt-get update
sudo apt-get install gdb
sudo apt-get install openocd
Then install java:
sudo apt install default-jre
Then install eclipse itself: Go to their download page: [eclipse
20](https://www.eclipse.org/downloads/download.php?file=/technology/epp/downloads/release/2019-03/R/eclipse-cpp-2019-03-R-linux-gtk-x86_64.tar.gz)
and then go into you download folder and unzip the file.
tar -zxvf "your-downloaded-file".tar.gz
and start up eclipse:
"YOUR-UNZIPPED-FOLDER"/.eclipse
#### Installing required Eclipse Plugins
Install the C++ development tools and GNU MCU plugin by following the
instructions [here](https://gnu-mcu-eclipse.github.io/plugins/install/).
- C++ Development - Follow the instructions under the header \'CDT\'.
- GNU MCU plugin - Follow the instructions under the header \'Plug-ins
install/update -\> The Eclipse Marketplace way\'
#### Import Crazyflie Firmware
First import the
[crazyflie-firmware](https://github.com/bitcraze/crazyflie-firmware)
into eclipse:
- File > import...
- C/C++ > Existing Code as Makefile Project -> Next
- Give it a name
- Existing Code Location > Browse... > //Look for the firmware folder//
- //Toolchain for Indexer Settings// can be ignored.
- Finish
#### Setting up Eclipse Debugging environment
- Go to: Run \> Debug Configurations\...
- Double click \'GDB OpenOCD Debugging\'
Now input the following settings in the debug configurations:
##### Main
Insert the filepath to the cf2.elf file to _C/C++ Application_.
##### Debugger
check the following settings: OpenOCD setup -\> Config options: \<code\>
-f interface/stlink-v2.cfg -f target/stm32f4x.cfg -c init -c targets
\</code\> GDB Client Setup:
- Executable name: Filepath to gdb toolchain
- Commands: \<code\> set mem inaccessible-by-default off \</code\>
##### Startup
##### Hit Debug!
If you don\'t see any errors, eclipse should go to an dedicated
debugging environment automatically and it automatically halts the
crazyflie\'s firmware before it goes into the main function of
src/init/main.c. Press F8 or Run \> Resume to let it continue and place
a breakpoints anywhere in the code (double clicking just in front of the
line in the gray area or press Shift+Ctrl+B). Now you should be able to
read out the values of the defined variables at that very position.
---
Make sure that your cf2.elf is the
same as the one you uploaded to the crazyflie!
---
### Mac OS
Install gdb and openocd
brew install gdb
brew install open-ocd
Install java JDK [java
download](https://www.oracle.com/technetwork/java/javase/downloads/index.html)
Download eclipse [eclipse
download](https://www.eclipse.org/downloads/download.php?file=/oomph/epp/2019-06/R/eclipse-inst-mac64.dmg)
Choose destination folders - Install
Run eclipse and choose work folder
##### Installing required eclipse Plugins
The rest is the same as for Linux. Make sure that the arm-none-eabi-gcc
is properly installed and its path is configured in the _debug
configurations_.