Add mechanisms to prevent flashing the wrong hex file.

[ahtn]

Issue

The flasher should display a warning if a hex file is not intended for the current mcu/board. Since there isn't really a way to add metadata to hex files, it will be necessary to either use the file nameor by extending the hex file format. Extending the hex file format is probably the more robust solution, but the extra data might need to be removed to flash the file with external tools.

Recover from loading a bad hex file

If you accidentally load a bad hex file, you can force the device to enter bootloader mode by following these steps:

1. Connect the USB port.
2. Short the GND and RST pins of the board once.
3. Open the flasher and program the new hex file.