How to use stm32l4 from IAP jump to bootloader

[1123]

I have bootloader initial position 0x08000000 and IAP 0x08004000 now.

First, I form bootloader jump to IAP code and it works fine.

But my jump back to bootloader will stop.

Maybe I have a lot of IAP function enable.

So I want to ask, besides __disable_irq() close NVIC, and any other way to deinit other functions?

Because I use __disable_irq(),but it seem isn't effect.

when i back to bootloader code of GPIO inti funaction , it already haven't stop.

[Tesla DeLorean]

Understand that __disable_irq() has a different effect than actually disabling the interrupts in the peripherals which you have enabled.

You're going to need an __enable_irq() somewhere if you ever want to see them again.

The loader/app need to set SCB->VTOR appropriately.

You can't transfer control from within an IRQ Handler, or related Callback function. Similarly an RTOS using System/User execution contexts.

[Alex R · Accepted solution]

Please take a look at the following information:

ARM: How to write a bootloader

http://www.keil.com/support/docs/3913.htm

[1123]

Thank you, the problem has been solved.

[Alex R]

Good!

Please let us know how you fixed the issue, as this helps the community if someone runs into the same issue in the future.

Thanks.

[1123]

I refer to the URL provided by Alex: How to write a bootloader

Before the jump,first you must Disable all enabled interrupts in NVIC.

code : NVIC->ICER[ 0~7 ] = 0xFFFFFFFF ;

After Disable SysTick and clear its exception pending bit, if it is used in the bootloader.

code : SysTick->CTRL = 0 ;

SCB->ICSR |= SCB_ICSR_PENDSTCLR_Msk ;

finally the user application into SCB->VTOR register.

This site has more detailed content.

If you are interested, you can refer to it.

THX.