Not necessarily. It can just test the resistance of the port/cable to see if anything is there. The first device (power provider) to detect the cable can say "o

Not necessarily. It can just test the resistance of the port/cable to see if anything is there. The first device (power provider) to detect the cable can say "ok, I got plugged in first" and then tell the other device (the consumer) that when they try to negotiate power delivery. That doesn't require maintaining state in the cable itself, just that the devices be able to detect the cable when it's plugged in (even without the other end connected). Cable detection: http://blog.teledynelecroy.com/2016/02/usb-type-c-cable-detection.html http://blog.teledynelecroy.com/2016/02/usb-type-c-cable-dete... Overview of USB power delivery negotiation: https://www.embedded.com/usb-type-c-and-power-delivery-101-power-delivery-protocol/ https://www.embedded.com/usb-type-c-and-power-delivery-101-p... And then after the initial connection, the devices can renegotiate their roles if you want to reverse the charge. It's great when it actually works. In the real world there are so many incompatible implementations that USB-C is a real clusterfuck.