STM32F303VET6 Jump to Bootloader
Hello,
As part of a new project, I'd like to use DFU mode for programming my STM32F303VET6.
I have a button that controls BOOT0. If the button is pressed during the microcontroller reset, there's no problem; I successfully enter DFU mode and can reprogram without any issues.
I'd like to be able to perform this step without any physical intervention on the board, but rather by creating a 'jump' from my application to the internal ST Bootloader.
My board is connected to the PC via a CDC connection. Using HyperTerminal, I send a command that calls a JumptoBootloader function.
My function is as follows:
void JumpToBootloader(void)
{
// 1. Stop USB peripheral
RCC->APB1ENR &= ~RCC_APB1ENR_USBEN; // Disable USB clock
RCC->APB1RSTR |= RCC_APB1RSTR_USBRST; // Reset USB
RCC->APB1RSTR &= ~RCC_APB1RSTR_USBRST;
// 2. Put USB pins (PA11/PA12) in analog mode
RCC->AHBENR |= RCC_AHBENR_GPIOAEN;
GPIOA->MODER |= (3U << (11 * 2)) | (3U << (12 * 2)); // Analog mode
// 3. Disable all interrupts
__disable_irq();
for (int i = 0; i < 8; i++)
NVIC->ICER[i] = 0xFFFFFFFF;
// 4. Stop SysTick
SysTick->CTRL = 0;
SysTick->LOAD = 0;
SysTick->VAL = 0;
// 5. Reset clock configuration
HAL_RCC_DeInit();
__DSB();
// 6. Set MSP to bootloader's initial stack pointer
uint32_t bootloader_addr = 0x1FFF0000; // System Memory for STM32F303
uint32_t msp = *(volatile uint32_t *)bootloader_addr;
__set_MSP(msp);
// 7. Optional: set vector table offset
SCB->VTOR = bootloader_addr;
// 8. Jump to bootloader reset handler
void (*bootloader)(void);
bootloader = (void (*)(void)) (*(volatile uint32_t *)(bootloader_addr + 4));
bootloader();
}
Unfortunately, I can't debug it. All I know is that the card seems to be malfunctioning; the USB connection is no longer recognized, and no device is visible in Windows Device Manager after unplugging and replugging the USB cable.
Do you have any ideas?