Arduino Uno not working as usb HID interface

Question

I have an arduino uno rev 3 and it works perfectly fine. I the OS I am using is Kali Linux 2.0 and you can upload everything as normal to the arduino. I am following this tutorial:Arduino Uno as usb HID interface device to use my arduino uno r3 as a hid device. After I upload the

Arduino-keyboard-0.3.hex

file, I plug cycle the board and I try uploading the example blink program. It always says:

Serial Port /dev/ttyACM0 not found.
Retry the upload with another serial port?
/dev/ttyS0

the /dev/ttyACM0 is my default arduino port and /dev/ttyS0 is one of my usb devices that is plugged in. Neverless, I tried uploading but it says board isnt responding. Can someone help me with this please?

Answer 1

You have reprogrammed the ATMega16U2 chip to be a HID device. Thus it no longer functions as a serial interface between the Atmega328P and your computer. You need to reflash the firmware on the ATMega16U2 to return to normal operation.

I have instructions for how you might to this on my bootloader uploader page. In brief, you need to put the original hex file back:

sudo dfu-programmer atmega16u2 flash Arduino-atmega16u2-Uno-firmware-Rev3.hex

There are other ways of turning your Uno into a HID device. Search for "Virtual USB Arduino".

More easily, get a Arduino Leonardo or Arduino Micro which are designed for this sort of thing.

---

Yes but how can I use it as a HID? ... it cannot detect it so how would I be able to upload code to it ...

What is "it" here? Look at this photo:

There are two processors on the Uno. It sounds like you have reflashed the ATMega16U2. Do you want to use the ATMega16U2 as a HID or the Atmega328P as a HID? They need totally different techniques.

Once you reflash the ATMega16U2 you can't "get to" the Atmega328P via the USB interface.

On the page you linked there is a workflow for programming the ATMega16U2. Are you following it? If so, which part is not working for you? If not, why not?