I have a project that was previously using STM32F411, and I am trying to swap over to using a STM32F412 (UQFN48, so pin compatible).
I thought I should be able to use the STM32F411 firmware on the STM32F412 (just not using the extra RAM/flash). I can flash it over USB DFU (so the hardware works) and the firmware itself runs fine (so clock speeds are fine), but USB does not work on it.
Does anyone know what changed on USB between chip versions that would stop the F411's code from working on F412? Is it just a matter of flipping some bits in a register?