Is it possible to have a custom bootloader in any sector?

[Kenji1]

Hi Team

I'm working on custom bootloader.

And I want to know if it possible to locate a custom bootloader in any sector.

Is it okay if the boot loader is not in the first address of FLASH 0x08000000?

[My Conditions]

IDE: STM32CubeIDE

MCU: STM32F405RG

[thundertronics.com]

Check if there is a "boot address" in option bytes (probably does not exists on this MCU).

Put boot loader at 0x08000000, check some condition during ~100ms after boot and proceed to main application in sector 1. Sector 0 (bootloader) may be write protected to keep device from being bricked during firmware update.

[MM..1]

Exactly normal no, but you can use bigger system technology bootloader level 0 , in addr from mcu start this jump to any sector bootloadeer level 1 and here you start to app....

[Tesla DeLorean · Accepted solution]

The F4 assumes bootable code/vector table is located at the base of FLASH (or ROM/RAM depending on mapping via BOOTx pins)

The H7 has some more options, but your bootloader needs to reside in the first 16KB FLASH block. You can put your App code anywhere you like deeper into the FLASH memory.

[Kenji1]

Hi, everyone!

Thank you for the reply.

I tested some codes, and F4 needs to locate the boot code on base address of FLASH.

Thanks.