Black Magic/DroneCode Probe

The Black Magic Probe is an easy to use, mostly plug-and-play, JTAG/SWD debugger for embedded microcontrollers. Since the Black Magic Probe is a generic debug probe, you will need an adapter to connect to Pixhawk flight controllers, which can be purchased here:

• Drone Code Debug Adapter (1 BIT SQUARED).

Dronecode Probe

The Dronecode Probe is a specialization of the Black Magic Probe for debugging PX4 autopilots.

The probe's USB interface exposes two separate virtual serial port interfaces: one for connecting to the System Console (UART) and the other for an embedded GDB server (SWD interface).

The probe provides a DCD-M connector cable for attaching to the Pixhawk Debug Mini.

:::note The 6-pos DF13 connector that comes with the probe cannot be used for SWD debugging (it is for using the System Console). :::

Using the Probe

:::note To debug STM32F7 or later (FMUv5 and newer) the Dronecode probe / Blackmagic probe likely requires a firmware update. You can find how to update the blackmagic probe here. :::

To use a Dronecode probe with GDB, start GDB with the exact ELF file that is currently flashed on the autopilot:

arm-none-eabi-gdb build/px4_fmu-v5_default/px4_fmu-v5_default.elf

Then, you have to select the Dronecode probe interface, on Linux this is e.g.:

target ext /dev/serial/by-id/usb-Black_Sphere_Technologies_Black_Magic_Probe_f9414d5_7DB85DAC-if00

Then you scan for the target:

monitor swdp_scan

And you should see something like:

Target voltage: 3.3V
Available Targets:
No. Att Driver
 1      STM32F76x M7

Note that for some autopilots it shows 0.0V but the subsequent steps work nevertheless.

You can now attach to that target:

attach 1

And now you should be connected.