Serial Custom Bootloader

Design description

The goal of this serial custom bootloader project is to enhance understanding of bootloader software for microcontrollers, particularly those based on ARM Cortex-M. It involves developing simple custom commands and communication protocols to establish a link between the microcontroller and a host PC.

Host communication

Simple bootloader protocol

Packet Format

Header packet

	SOF	TYPE	LEN
SIZE (bytes)	1	1	2

Data packet

	DATA	CRC
SIZE (bytes)	4 - 1024	4

Packet Type

• START: to indicate the start of firmware download.
• STOP: to indicate the end of firmware download.
• RESP: to respond the host on packet reception based on the validation.
• CONF: to send the firmware configuration includes (version, size, crc) etc.
• DATA: to send the actual firmware binary packets.

SBP host tool

The host tool to flash the bin into the microcontroller using Simple Custom Bootloader Protocol(SBP).

python3 Utils/boot_tool.py <app_binary_path> <app_version>