Arduino MKR Wifi 1010 no more COM

I have an Arduino MKR Wifi 1010, everything was working fine.

I have upload a sketch and I got a message "Low memory available. Stability problems may occurs"

Since then, I'm not able to see the device on the COM ports...
I try to change cable, reboot device, reboot pc, nothing work. I try to connect another Arduino MKR Wifi 1010, this one is connecting without a problem.

Is my Arduino device definitely burned? is there a way to do a "hard reset" of the device?

The tricky thing about the boards with native USB functionality like your MKR WiFi 1010 is that the USB code that creates the CDC serial port is running on the same microcontroller as your sketch. This means your sketch code can break the USB code, or stop it from running, causing the port to go missing.

Fortunately, there is an easy way to recover from this situation:

  1. Press and release the reset button on your board quickly twice. You should now see the LED on the board pulsing, which means the bootloader is running. The double press causes the bootloader to run indefinitely (until the board is reset, powered off, or an upload is done), which means you don't need to get the timing of the reset just right.
  2. Select the port of your board from the Tools > Port menu. The port number may be different when the bootloader is running so don't assume you already have the correct port selected.
  3. Start an upload in the Arduino IDE.

The upload should now finish successfully. After this, you should be able to go back to doing normal uploads without needing to press the reset button. If you still need to do the reset trick to do uploads after this, the problem may be caused by your code. You can verify this by uploading a simple sketch like File > Examples > 01.Basics > BareMinimum.


wow!!!! many thanks for the trick...; in fact it perfectly works.

Now that I know about the possible 'blocking' of the code I will program in a different way my sketches!!

again, many thanks!

You're welcome. I'm glad to hear it's working now. Enjoy!