1.5.1 Configuring the NVM Host applications

Path of the NVM host applications within the repository are

  • apps/i2c_bootloader/

  • apps/i2c_fail_safe_bootloader/

  • apps/i2c_bootloader_wlcsp/

Generating Hex Image pattern used by NVM Host application

Follow below steps only when existing test_app is rebuilt or any other application is to be bootloaded

  1. Open the application project to be bootloaded in the IDE

    • If existing test application has to be built open test_app/firmware/*.X

  2. Build the application project to generate the binary (Do not program the binary)

  3. Convert the generated binary (.bin file) to a header file containing the image data in a C style array:

    • On a Windows machine, open the command prompt and launch the btl_bin_to_c_array.py utility to generate a header file containing the image data in an array

      python <harmony3_path>/bootloader/tools/btl_bin_to_c_array.py -b <binary_file> -o <hex_file> -d <device>

    • Refer to btl_bin_to_c_array utility for converting the binary to C array in hex format

      bin_to_c_array

  4. Add the application hex header file generated in above step to the test app images path of the I2C embedded host application host_app_nvm/firmware/src/test_app_images/

    • Example:

      • If the application hex header file generated is for sam_d21_xpro.X project, Name it as image_pattern_hex_sam_d21_xpro.h and place it in above path

Configuring the NVM Host application

Follow below steps only when Host development kit is different than Target Development Kit

  1. Open the host_app_nvm/firmware/*.X project in MPLABX IDE

  2. Open the "user.h" file as shown below:

    i2c_bootloader_host_app_nvm_user_ide

  3. Open test_app_images/i2c_target_boards.h to get predefined macros of supported Bootloader Target Devices

    i2c_bootloader_host_app_nvm_target_board

  4. In the "user.h" file specify the Bootloader Target Device used using the predefined macros from test_app_images/i2c_target_boards.h

    #define APP_I2C_BOOTLOADER_TARGET_DEVICE     SAM_D21_XPRO
    i2c_bootloader_host_app_nvm_user_config

  5. Open test_app_images/i2c_target_config.h to get predefined configuration of supported Bootloader Target Devices

  6. Navigate to the #if block for the specified Bootloader Target Device and verify the below settings are as expected.

    i2c_bootloader_host_app_nvm_target_config

    • APP_HEX_HEADER_FILE: Relative path to the generated header file containing the application hex image in an array

    • APP_I2C_SLAVE_ADDR: I2C client address

    • APP_ERASE_PAGE_SIZE: Erase page size of the target (target = MCU being programmed)

    • APP_PROGRAM_PAGE_SIZE: Program page size of the target (target = MCU being programmed).

      • The macro can either be set to the program page size or can be set to the size of the erase page size of the target.

      • In the demo example, the macro is set equal to the size of the erase page.

      • On embedded host where RAM is limited, the macro may be set to the actual program page size to reduce the RAM used to hold the program data.

        • For example, for SAM D20, the macro can be set either to 64 (program page size) or 256 (erase page size)

    • APP_IMAGE_START_ADDR: User application start address (This value should be same as the application start address specified in Application Configurations steps).

      • If the bootloader itself is being upgraded then the APP_IMAGE_START_ADDR must be set to 0x00 (start of bootloader)

      • Ensure that the bootloader and application are also configured with the same value of user application start address