ETRA SBC provides two USB ports, one HOST and one OTG:
* J17 is a standard USB HOST 2.0 Type A connector
[[File:{{{nome-som}}ETRA-EVB-USB-HOST-connector.png|thumb|center|500px|USB HOST connector]]
* J16 is a micro-AB type receptacle for a USB OTG connection: this interface can operate in Host mode and Device (peripheral) mode
[[File:{{{nome-som}}ETRA-EVB-USB-connector.png|thumb|center|500px|USB connector]]
===Signals ===