RP2040: Using Arduino C/C++ instead of CircuitPython

I and others have run into a problem using RP2040 boards like the Adafruit ItsyBitsy RP2040 with the Arduino C/C++ IDE.

After compiling, the upload of the code to the board will not complete. There are two fixes:


1) Check that your antivirus isn't blocking "rp2040upload.exe" from running. If it is, add it to the antivirus "whitelist" so it will be ignored next time.


2) Navigate to "C:\Users\<yourname>\AppData\Local\Temp" and look for the latest "arduino_build_xxxxxx" folder.  (There will be a unique folder for each different Arduino board you are using.)

Using "Blink.ino" as an example, look for your file name ending in ".uf2". That would be "Blink.ino.uf2" in our example.

If you don't see RPI-RP2 as a logical drive in your system, hold down the BOOT button while momentarily pressing the RESET button on your Arduino board; this should make it available.

Copy the ".uf2" file to this drive. Win10 should reboot the logical drive once the copy is completed. If it doesn't reboot, press the board's RESET button.  The program you manually uploaded to your Arduino board should now be running normally.


I and others have logged this as a concern with Adafruit via their Forum but I don't expect a near-term fix. Ada's focus seems to be with CircuitPython lately and not Arduino C/C++.


Updated 2022-03-22 @ 8am