@Alex-Kushleyev Found the reason why it was skipping. In /px4-firmware/src/lib/parameters/CMakeLists.txt there is a line that skips all modules that match 'pwm_out'. I was able to disable that for PCA9685. Once I disabled the module.yaml file being skipped it worked. No need for the .c file (which makes sense, that is just the old way to do the .yaml)