Adding Profiles for 20 and 16 Mhz External clock (not crystal) - atmega32

[lindoran]

Good afternoon,

I was wondering if you would be interested in a pull request to add/change the following to boards.txt for the atmega32/a?

32.menu.clock.16MHz_external=External 16 MHz (crystal) 32.menu.clock.16MHz_external.upload.speed=115200 32.menu.clock.16MHz_external.bootloader.sut_cksel_bits=111111 32.menu.clock.16MHz_external.bootloader.ckopt_bit=0 32.menu.clock.16MHz_external.build.f_cpu=16000000L

32.menu.clock.16MHz_clock=External 16 MHz (clock) 32.menu.clock.16MHz_16clock.upload.speed=115200 32.menu.clock.16MHz_16clock.bootloader.sut_cksel_bits=000000 32.menu.clock.16MHz_16clock.bootloader.ckopt_bit=1 32.menu.clock.16MHz_16clock.build.f_cpu=16000000L

32.menu.clock.20MHz_external=External 20 MHz (crystal) 32.menu.clock.20MHz_external.upload.speed=115200 32.menu.clock.20MHz_external.bootloader.sut_cksel_bits=111111 32.menu.clock.20MHz_external.bootloader.ckopt_bit=0 32.menu.clock.20MHz_external.build.f_cpu=20000000L

32.menu.clock.16MHz_20clock=External 20 MHz (clock) 32.menu.clock.16MHz_20clock.upload.speed=115200 32.menu.clock.16MHz_20clock.bootloader.sut_cksel_bits=000000 32.menu.clock.16MHz_20clock.bootloader.ckopt_bit=1 32.menu.clock.16MHz_20clock.build.f_cpu=20000000L

This would add sourcing a clock on a single pin in situations where the clock is coming from a discrete oscillator, I don't know if it could be further added to the drop downs in a way that offers this to the other chips as well. This was just a quick and dirty to get what I needed, and I only looked into just the atmega32.

also attached here if you are interested in just manually dropping the change

boards.txt

[lindoran]

after trying with the default clock settings -- this seams to work in any case ~ these changes aren't needed