using atmega328 vs 328P on Arduino Uno bd


I purchased ATMEGA328 instead of ATMEGA328Ps. I was able to program the bootloader, using Minicore breadboard solution. However, when I now put that micro on the Uno, and I try to compile the example sketches (used known good ones to ensure everything is working), I get the error in the signature of the device. It expects the device on the UNO to be a 328P and I'm getting the signature of the 328.

I tried adding the 328 device to the boards.txt, but it is read only, and I can't figure out how to override its file protection.

The error message suggests I override the signature with -F option on the avrdude command, but I can't figure out where to add this option (looking through the avrdude config file, etc).

How can I add support for this micro on the UNO? Can I create another board.txt file that it can then use to tpass the "right" info to avrdude ? There must be a way.....

Outside my area of expertise but adding minicore package might be a solution and using that for compile and upload.

One reason why you get the read only message might be that you're using the Windows store version. You don't provide the details so it's just a guess.

With sufficient permissions, you should be able to change the permissions on the boards.txt file.

Thanks @sterretje, this is running on my personal PC, so I am the admin with full privileges, and I still can't seem to override the write protection! I had never run into that.

You are right, though. I was able to compile using the MiniCore 328 board as the target. So for now, I can work arouind the issue. However, the "right" solution, in my opinion, would be to add the board to the board.txt file --ie, an UNO with a ATMEGA328.

Any idea how to pass arguments to the avrdude when it is invoked from the arduinoISP sketch?

Thanks for you input!