That's the power of the Pico - the bit-banging happens in the PIOs, not the main cores. So idling takes no CPU (the idle symbols are pre-calculated and DMAed in

That's the power of the Pico - the bit-banging happens in the PIOs, not the main cores. So idling takes no CPU (the idle symbols are pre-calculated and DMAed into the PIOs, which do the bit banging), and transmission only needs the CPU for framing and encoding, not the timing sensitive / interrupt driven bit-banging stuff. The ADC example in the README is pretty fun; being able to stream data out to a PC at a high rate over a standard interface is always useful in some niche use case, and I don't think anyone has managed High Speed USB over PIO (yet?) so this is likely to be the fastest way.