but I am trying to interact with a system that starts talking on the bus ~750ms after power on, and naturally the bootloader delay gets in the way
Instead of hacking text files,
# this defines how the entry will show up in the IDE menuatmega328ispmk2.name=Arduino ATmega328 AvrISPmkII# maximum upload size = maximum flash size since we do not need a bootloader anymoreatmega328ispmk2.upload.maximum_size=32768# which programmer to use# avrispmkii exists already in programmers.txt # if you possess a different one you might need to add an entry there as wellatmega328ispmk2.upload.using=avrispmkii# target controller, relevant for the controller AND the compileratmega328ispmk2.build.mcu=atmega328p# target frequency, irrelevant for the programmer, will be picked up by the compiler thoughatmega328ispmk2.build.f_cpu=16000000L#atmega328ispmk2.build.f_cpu=1000000L# no clue what this does but the other entries use this as well :)atmega328ispmk2.build.core=arduino
Uploading using a programmer (from within the IDE without editing any preferences files)
What if someone was given the pre-compiled hex file by someone else?