Zero to main(): How to Write a Bootloader from Scratch | Interrupt

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Francois thanks for your prompt reply. I still have some confusion, would appreciate if you can clarify. Before posting I google all the topics so will be precise.

  1. file line 214. In this project you compile both app and bootloader (at the same time, right?). Both has main function. Why line 214 calls app’s main, not bootloader’s main?

  2. Tiny question.
    you and many other projects use attribute ((section(“.vectors”))) before table assignment, though documentation states to use it in between e.g. struct duart a attribute ((section (“DUART_A”))) = { 0 };.
    Is there any new spec which covers such usage?

  3. I mostly understand, but still not clear why we need own vector table (not 2, right? I mean we have all addresses for bootloader and app interrupts but only single vector table exists for controller) for app and bootloader. May be you can give simple example? The post you mentioned somewhere in your blog provide some explanation

So long as the user program doesn’t go and mess with the VTOR, any interrupts that occur after the user program re-enables interrupts will cause the NVIC to use the user program’s table to determine where the handlers are. Isn’t that awesome?

but not sure I understand it right way.