1.6.1 How the USB Device HID Bootloader Library Works

The USB Device HID Bootloader firmware communicates with the Unified Host application running on Host PC by using a predefined communication protocol.

The USB Device HID Bootloader works in two different modes:

Basic Mode

• This mode is supported for all the devices

• Resides from:

  • The starting location of the Flash memory region for Cortex-M based MCUs

  • The starting location of the Boot Flash memory region or Program Flash memory region for MIPS based MCUs devices

• The Bootloader performs Flash erase/program/verify operations with the application hex sent from host PC using the Unified Bootloader Host Application while in the Firmware Upgrade mode

  • Bootloader always performs Flash operation from the address received via hex record

  • The application can use the entire Flash memory region starting from the end of bootloader space

• Jumps to the application once programming is completed

Live Update Mode

• This mode is supported for the devices which have a Dual Bank Flash memory

• Resides from:

  • The starting location of the Flash memory region of both the banks on Cortex-M based MCUs along with application code

  • The starting location of the Program Flash memory region of both the banks for MIPS based MCUs devices along with application code

• The Bootloader task performs Flash erase/program/verify operations with the application hex sent from host PC using the Unified Bootloader Host Application in the Inactive bank

• Performs a bank swap and reset to run the application programmed in inactive bank on application task request