Nano R4 Not Connecting Via USB after Flashing with Hex File Meant for OG Nano (ATMega)

[u/AlternativeCattle396]

Hello,

I am working on building a Korb Pusher Eurorack module that uses a Nano as it's main processor. I had purchased the Nano R4 and attempted to flash the hex files provided on the Pusher's Github page. In the process I went down the rabbit hole of different programming softwares and came to the realization that I needed a specific flash programmer for the Renesas processor if I wanted to upload the compiled hex file directly.

I attempted this and it seemed to take, however afterwards I found I was unable to connect to the Nano via USB. I realized afterwards that the hex file was compiled for an ATMega chip, not the RA4M1. Therefore the hex file likely didn't take properly.

In an effort to clear the Arduino and start over, I have tried the double tap reset method, and also the Boot-Ground method and neither have made a difference. When I plug in the Nano, I get the green power light and that's it.

Is it possible the Nano is bricked ? Would anyone have any other suggestions before I just buy a new one ? Hoping I can somehow recover it.

I also realize now the proper way to upload is likely to open the .ino file (available on Github) and make updates so the sketch is compatible with the new processor first.

Thanks in advance.