User guide

Atmel AVR2054: Serial Bootloader User Guide [APPLICATION NOTE]
8390D−WIRELESS−03/2015
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4.1.2 Loading application firmware to an MCU
To program an MCU using serial bootloader the following steps shall be done:
1. Connect an MCU with the embedded bootloader firmware on it to a PC via serial connection. For detail refer to
Section 2.1 as well as documentation of the development kit or the software provided with it.
2. For the GUI version of serial bootloader run the application by double-clicking the bootloadergui.exe file and
the control dialog as shown on Figure 4-1 will appear. For the console version just start command line from the
Bootloader PC tool installation directory (see Section 4.1.3 for more detail).
3. Specify uploading parameters:
a. Select the connection type. For all devices except Atmel SAM3S select
Serial, while for SAM3S select
USB.
b. Select the port from the drop-down list.
There is a restriction on the size of firmware downloadable by serial booting process. Serial bootloader cannot rewrite
the area where the bootstrap code resides.
4. Press the Upload button if Bootloader PC GUI tool is used. For the console bootloader press Enter on the
keyboard to start uploading.
5. Press the HW reset button on the device if requested. The Bootloader PC tool will be waiting for approximately
30 seconds for the button to be released. If this does not happen, programming will be aborted.
6. The Bootloader PC tool will indicate the programming progress. Once loading is finished successfully, the
device will be restarted automatically. If loading fails, the Bootloader PC tool will indicate the reason. In case
the new image upload fails (for example, because of random communication errors) the device should be re-
programmed. It the reprogramming does not resolve the issue then the previously programmed code image in
the device may be corrupted. The device should be erased and reprogrammed via JTAG.
Figure 4-1. The Bootloader PC tool main GUI window.