Yeah, that's a better way to do it. I've been following rust for embedded with great interest but I'm not so sure the HAL work is really going in a good direction. There seems to be a lot of awkward design decisions going into the interfaces (and to be clear, designing even a simple GPIO interface which satisfies even most users is Hard, let along anything which works for something like a serial port). I've a feeling if I started using it in anger I would fairly quickly just write my own.