I own an Adafruit USB to TTL Serial cable. I have been able to access the serial console on the Raspberry Pi using this. I am wondering whether this cable (amazon.com link) could be used for UART debugging as in this video (Hack All The Things: 20 Devices in 45 Minutes (from 2014's DEFCON)) demonstrates.
This is the first time I've ever thought about hacking hardware other than the Raspberry Pi. Any guidance would be greatly appreciated.