STM32 USB programming, jump to bootloader for DFU

Question

I was having trouble on the STM32L462xx with setting the device up for flashing over USB without having access to the BOOT0 pin. Going off of the tutorial on the ST site didn't seem to accomplish the task. Has anyone successfully set the STM32L4 into bootloader mode from software?

https://stm32f4-discovery.net/2017/04/tutorial-jump-system-memory-software-stm32/

Answer 1

I was able to set the device into a mode which it can be programmed with STM32Cube Programmer or the DFU-util program using the following code. This is partly a signal boost for this programmers solution which went against the ST tutorial on their site saying how to put jump the device memory to bootloader for USB programming

https://github.com/markusgritsch/SilF4ware/blob/94bb679119a0b9879fedc62a5e22f40623433242/SilF4ware/drv_reset.c

void jump_to_bootloader(void)
{
    __enable_irq();
    HAL_RCC_DeInit();
    HAL_DeInit();
    SysTick->CTRL = SysTick->LOAD = SysTick->VAL = 0;
    __HAL_SYSCFG_REMAPMEMORY_SYSTEMFLASH();

    const uint32_t p = (*((uint32_t *) 0x1FFF0000));
    __set_MSP( p );

    void (*SysMemBootJump)(void);
    SysMemBootJump = (void (*)(void)) (*((uint32_t *) 0x1FFF0004));
    SysMemBootJump();

    while( 1 ) {}
}