4.2.4 USB

The SAM R21 Xplained Pro has a Micro-USB receptable for use with the SAM R21 USB module. To be able to detect when a USB cable is connected, a GPIO/ADC is used to detect the VBUS voltage on the connector.

Table 4-9. USB Connections
Pin on SAM R21USB
PA07VBUS Detection
PA24USB D-
PA25USB D+