Feature Request: Allow PWM outputs to be used as discrete GPIO #100
Description
Sorry for a couple of incomplete feature requests; these are functions that I'd like to have available myself, but haven't had time to put together a PR on them yet. As a result, if it's alright, there might be a couple of subsequent posts on these issues with background information/references until such as time that I can implement those/create the appropriate PR.
One of those functions is using the PWM outputs from the PCA9685 chip as a discrete on/off GPIO toggle, which can be useful for a number of simple peripherals such as indicator LEDs, as mentioned by another member of the community in a issue on the BR forum here.
It looks like Adafruit's servo board based on this chip has some functionality similar to this, and the underlying Rust library that navigator-rs is using also appears to have some basic documentation on doing this as well.
The signaling PWM behavior is implemented in this library via the PwmBehaviour trait on the Pca9685Device struct, and while there's something like LedBehaviour that could feasibly work, I think that would be unclear, and it might be better to extend the trait system to have something like GpioBehaviour instead.