Question: How do I add a custom clock option for ATMega328P in the Arduino IDE menu?

[sidharthbhatia]

Hi @MCUdude,

Thanks a lot for the awesome core! It really simplifies a ton of things.
I am using the core version 3.0.2 with Arduino IDE 2.3.2 and I want to add a new clock option to the Clock selection menu for the ATMega328P. I want to call it 2MHz_16MHz_external. Using this, I intend to activate the CKDIV8 fuse bit to run the MCU at 2MHz with the 16MHz external oscillator found on most ATMega328P Arduino boards.
I followed the changes you did in your recent commit Add 9.216 MHz clock. Here are the changes that I did to the boards.txt file:

328.menu.clock.2MHz_16MHz_external=External 2 16 MHz
328.menu.clock.2MHz_16MHz_external.upload.default_speed=9600
328.menu.clock.2MHz_16MHz_external.bootloader.low_fuses=0b0111{bootloader.cksel_bits}
328.menu.clock.2MHz_16MHz_external.build.clkpr=
328.menu.clock.2MHz_16MHz_external.build.f_cpu=2000000L

Even after doing these changes and restarting the Arduino IDE, I am not able to see this option in the menu. I also tried changing the name of an existing clock option, e.g. changing External 2 MHz to External 2 MHz Osc but no change seems to be reflecting in the menu. However, when I change the fuse bits for the External 2 MHz and burn the bootloader to the MCU, I am getting the correct fuse values getting written to the MCU.

I can, although, see the updated options in the Arduino IDE 1.8.13.

Can you please let me know what else I need to do here?

As an additional info, I also tried deleting the cache and staging folders, which didn't work.

[MCUdude]

Hi!

I'm not sure what the problem is. I've installed MiniCore though the boards manager, and when editing the boards.txt located in the following path on my mac, the 2 16 MHz external option shows up without any issues:

/Users/hans/Library/Arduino15/packages/MiniCore/hardware/avr/3.0.2/boards.txt

[sidharthbhatia]

Hmm. That's strange. I tried removing and reinstalling MiniCore via the Arduino IDE boards manager, but I didn't get any success doing that as well. I could try uninstalling and reinstalling the Arduino IDE to see if that solves it.