Bootloader Library Help > Unified Bootloaders > How the Library Works > Bootloader Memory Layout > SAM Device Layout
MPLAB Harmony Bootloader Help
SAM Device Layout

The placement of the Bootloader and the application in flash memory should be such that the application will not overwrite the Bootloader, and the Bootloader can properly program the application when it is downloaded. 


  • Bootloader code is always placed at start of the flash address
  • The application code can be placed anywhere after the bootloader end address. The application start address should be Aligned to Erase Unit Size
  • As the Bootloader code requires the application start address to be mentioned at compile time, it should match in both the application and bootloader



The start address and the end address of the Bootloader and the application will vary for different devices. Refer to respective Data sheets for details of Flash memory layout. 



MPLAB Harmony Bootloader Help