1.2 I²C Bootloader

The I²C bootloader Library can be used to upgrade firmware on a target device without the need for an external programmer or debugger.

Features

• Supported Only on Cortex-M0+ and Cortex-M4 based devices
• Uses Harmony 3 I²C PLIB to communicate resulting in smaller bootloader size
• Supports Fail Safe update
• Takes Binary File as input
• Receives Binary from an I²C Embedded Host Device

Running From SRAM (For SAM Devices)

• Has capability to self update as it is running from SRAM

  

• At reset the bootloader Reset handler copies the entire bootloader firmware into SRAM from Start location and start executing from SRAM
• Once the application is called from bootloader, applications startup code takes control over SRAM and starts executing

I²C Bootloader Block Diagram

• I²C Event Processor Task:

  • This task is responsible for receiving data from Embedded Host through the I²C communication interface

  • The task polls and processes the I²C events

  • Based on the event received it gives control to I²C Host Write Request or I²C Host Read Request functions

  • This task is responsible for responding to the bootloader commands received

• I²C Host Write Request:

  • This function is responsible to handle any write requests coming from I²C host

  • It processes the commands received and notifies the status to I²C Event Process Task

  • If the command received is a Erase/Program/Verify command it gives control to the Flash Task

• I²C Host Read Request:

  • This function is responsible to handle any read requests coming from I²C host

  • It sends the current status to I²C host if the command received is Read Status

• Flash Task:

  • This task is responsible to Erase/Program/Verify the internal Flash memory with data packet received

  • The task uses the NVM peripheral library to perform the Unlock/Erase/Write Operations