User manual

Atmel AVR1939: XMEGA-C3 Xplained Getting Started Guide [APPLICATION NOTE]
42054A−AVR−02/2013
5
To avoid a file system corruption, the data logging is stopped on microSD while the USB is enabled. All sensor data
logged on the microSD card are stored in a file named dat_log_c3_xplained_xx.txt where xx will be incremented from
00 for each new session of sensors data storage on the card.
Figure 2-5. USB Mass Storage Class and removable disk content.
The CDC interface uses the native driver from UNIX
®
O.S., but requires a specific one on Windows
®
O.S. When the
USB feature is disabled, the Windows driver file is created by demo application on the microSD card. After USB MSC
startup or through another SD card reader, the atmel_devices_cdc.inf file can be selected to install the new USB CDC
interface.
After having installed the CDC driver, the Virtual COM port can be opened through a terminal.
Figure 2-6. USB Communication Device Class.
Note:
The Virtual COM port is not connected to a true RS232 COM port, thus the baudrate and parity parameters can
be ignored.
The demo application for the XMEGA-C3 Xplained is available through the Atmel Software Framework (ASF), version
3.5.0 or later. The demo application is available as an example project in Studio 6 and can be accessed by clicking File
-> New -> Example Project, and selecting “Demo application for XMEGA-C3 Xplained”. In-depth documentation for the
demo application is available in the Atmel AVR1940 XMEGA-C3 Xplained Software User Guide.
To modify the example code or write new code and compile it, you need a toolchain for the Atmel AVR microcontrollers
and an IDE to edit and debug code. Atmel provides both with Studio 6. More information about all available documenta-
tion and tools is available in the Chapter 4.