My computer will only recognize my Arduino Uno R4 after I press the reset button twice, putting it into DFU mode. The IDE displays it as Arduino R4 Minima on 1-2 under DFU ports. Here, I can upload sketches, but I can't use serial monitor, it gives this error: No monitor available for the port protocol dfu. Could not connect to 1-2 dfu port. If the Arduino is not in DFU mode, it won't even be recognized as a device by my computer, let alone show up in the IDE through a COM port. It's recognized as Santiago DFU in Windows device manager when in DFU mode.
What I have tried:
- Reinstalling Arduino IDE (latest version)
- Reinstalling the R4 library in boards manager
- Reinstalling the USB Serial (CDC) drivers using Zadig
None of those actions will change anything.
If you don't want DFU mode, press the reset switch ONCE. Now upload your sketch the usual way.
If that doesn't work, upload the Blink sketch and that should reset the DFU mode.
If none of those work there is a utility for my Mac, but if you have windows you will need to find something like dfu-util.
To confirm the board is in DFU mode run this cmd
dfu-util -l
Then reboot the board with
dfu-util -e
If all that fails, you will need to re-flash the board.
I tried uploading Blink while in DFU mode, and that fixed it. It seems like something was wrong in my original sketch, I don't know how that could have affected it.
Thanks for your help.
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Mark post #2 as the Solution so other users with the same issue can use that solution.