In order to activate bootloader on supported boards you must close with a jumper RB6 and RB7, available on ICSP connector, like showed in the following picture:
DRLoader is a windows executable and no requires others add-ons or runtimes. The GUI is very simple: there are only 2 buttons, a text area and a status bar:
On the top there is a blue label marked "Detect": it turns on when is connected a compatible board:
In the text area are indicated board model and firmware revision too. Update button is not enabled until a firmware revision is loaded.
To load new firmware, press "Open" button and browse for file named with suffix "DR_" and ".hex" extension (a valid name example is: "DR_aggiornamento1.hex"):
Once file is selected, GUI will show version and build date of new firmware:
Now "Update" button is enabled: by pressing it new firmware will be loaded into picmicro. Loading will be showed by a progress bar. At the end of the process (about 10 - 30sec), progress bar will be green-colored and a popup window will appear:
If popup window is not shown or progress bar is not green-colored an error has occured: in this case disconnect board, close DRLoader, Reopen DRLOader, reconnect the board and repeat the operations.
If USB cable is detached or there is an error on USB communication a specific error message will be shown:
In this case check USB connection and retry. Once update is terminated, remember to remove the jumper and reset the board.