1.5.1 Configuring the NVM Host Applications

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

     

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

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

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

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

   

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

   

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
   

   

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.

   

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