Atmel MCU Evaluation Kit AT32UC3L-EK AT32UC3L-EK Data Sheet

 

32150B-AVR-03/12 

Figure 3-16. Atmel AT32UC3L-EK USB interface logical view. 

The USB interface provides two features to the AT32UC3L-EK kit: 

• USB 

communication 

•  Power supply (see Section 

 for a description of that feature) 

The USB controller is the Atmel AT32UC3B1256. 

The AT32UC3B1256 comes pre-loaded with several firmware components: 

•  A USB DFU boot loader [accessible upon power up when the J12 header is closed 

(see 

, for the 

location of the J12 header)] to re-program the AT32UC3B1256 

•  A USB CDC-USART bridge (a USB CDC virtual com port) where every data 

character received from the USB is sent to the Atmel AT32UC3L064’s USART3, 
and every character received from the AT32UC3L064’s USART3 is sent to the 
USB 

•  A HID QTouch Debug firmware acting as a USB HID-USART bridge between AVR 

QTouch Studio (Section 

) and the AT32UC3L064’s USART3 

•  A tiny boot selector allowing the user to choose (using the USB MODE 

pushbutton) upon power up between running the virtual com port firmware or the 
HID QTouch Debug firmware. By default the HID QTouch Debug firmware will be 
running. See also Section 

The source code of this firmware is available in the Atmel AVR Software Framework 
(Section 

). 

The user interface of the USB interface block is made of: