GAH. working with the raspi pico just makes me angry because of how confusing and unhelpful it can be. like I wrote some code, which I know works (because I've used it before!) and I copy it onto the device. I reconnect the device and... it doesn't enumerate. it doesn't even error. it just acts like there's no USB there
which would normally suggest that there's some issue with the hardware but I can push the BOOTSEL and and reconnect and get it back into programming mode just fine!
and I can flash circuitpython onto it and have that work just fine too
ARGH my codebase has two copies of the known-working code and the code is identical but the CMakeFiles are different and one works and the other doesn't
@foone best guess: the one that doesn't work is likely not stripping the elf header after compilation, elf only works if you have a loader for it, if you want a raw executable(like to load as firmware) you gotta trim it off and start the code from the address of the _start symbol.
Don't know for sure obviously but that's the most likely culprit always in situations like this.
@foone pi pico uses a fully software implementation of USB (not hardware), so if the software doesn't work then it literally isn't USB and won't enumerate