Raspbery Pi-Pico Conversion to a Pico-Probe Part 1

This simple guide goes over programming your raspberry pi into a pico-probe with hopefully CMSIS-DAP support!

Raspbery Pi-Pico Conversion to a Pico-Probe Part 1

If this process is a little to much you can buy one on Amazon. They look to be selling quite quickly:

  • There can be a lot of complexity and moving parts. To help and to caveat these guides are 'over-explained' repeatedly on purpose.
  • If you buy a pre-canned one, it will already have a compatible .elf / .uf2 operating file installed (w/ hopefully JTAG) and the compatible RTOS system already installed.
  • Here is how to roll-your-own in the Linux environment.

Download the following github:

GitHub - raspberrypi/debugprobe
Contribute to raspberrypi/debugprobe development by creating an account on GitHub.
git clone https://github.com/raspberrypi/debugprobe
cd debugprobe &&  git submodule update --init

It will pull a bunch of files - include freetos...

mkdir build && cd build
cmake ..

Will actually produce an error (going by the git instructions)

We can set our environment variables a couple ways:

export PICO_SDK_PATH="/where/lives/pico-sdk"
# or 

One can find the pico-sdk here:

GitHub - raspberrypi/pico-sdk
Contribute to raspberrypi/pico-sdk development by creating an account on GitHub.

One was able to do the following after:


The -DDEBUG_ON_PICO is important you need it for the full JTAG support.

And finally (make it):


This made a fair bit of output basically:

Important part: You have two generated versions:

  • The one that works is debugprobe_on_pico.uf2

Next we can watch the lsblk as:

watch lsblk

And we can watch the message bus with:

dmesg -w

If you hold the BOOTSEL button while powering it on:

You will see in your dmesg -w bus something like:

And you will see your 'watch lsblk' shift as:

Now you can mount it requiring sudo:

sudo mount /dev/sdc1 /raspb
  • Mount /dev/sdc1 onto the directory location /raspb

And copy your .uf2 (some suggest .elf) from your build directory to your mounted point.

  • The raspberry pi pico will automatically reboot.
  • The proper dmesg -w should look as:
  • Note how it now says 'Product: Debug Probe on Pico (CMSIS-DAP)

Now onto Part II - Testing your pico-probe.

Raspbery Pi-Pico / Pico-Probe Testing and Work ups Part II
In this Part II guide we start learning the bells and whistles of a pico-probe being used in the OpenOCD environment.

Here is a nice diagram for wiring it.

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