Question
STM32F072CBT6 - Entering bootloader from application and USB (DFU) flasher
I have been able to use the below function to enter the bootloader from the Application and successfully flash a new firmware from the UART interface.
/**
* @brief Resets the microcontroller entering into the embedded bootloader
* to allow for upgrading the application's firmware
* @param run Safety variable
* @arg @ref TRUE To enable execution of the bootloader
* @retval None
*/
void Bootloader_Start(uint32_t run) {
void (*SysMemBootJump)(void);
/**
* Set system memory address.
*
* For STM32F072, system memory is on 0x1FFF C800
* For other families, check AN2606 document table 155 with descriptions of memory addresses
*/
volatile uint32_t addr = 0x1FFFC800;
if (run == TRUE)
{
// De-initialize all peripherals configured for this Application
HAL_TIM_Base_DeInit(&htim1);
HAL_TIM_Base_DeInit(&htim6);
HAL_TIM_Base_DeInit(&htim7);
HAL_TIM_Base_DeInit(&htim14);
HAL_TIM_PWM_DeInit(&htim15);
HAL_TIM_Base_DeInit(&htim15);
HAL_CRC_DeInit(&hcrc);
HAL_NVIC_DisableIRQ(DMA1_Channel1_IRQn);
HAL_NVIC_DisableIRQ(DMA1_Channel2_3_IRQn);
HAL_NVIC_DisableIRQ(DMA1_Channel4_5_6_7_IRQn);
HAL_DMA_DeInit(&hdma_memtomem_dma1_channel2);
HAL_PCD_DeInit(&hpcd_USB_FS);
HAL_UART_DeInit(&huart2);
HAL_UART_DeInit(&huart1);
HAL_ADC_DeInit(&hadc);
// Disable GPIO interrupts
HAL_NVIC_DisableIRQ(EXTI0_1_IRQn);
HAL_NVIC_DisableIRQ(EXTI2_3_IRQn);
HAL_NVIC_DisableIRQ(EXTI4_15_IRQn);
// Disable RCC, set it to default (after reset) settings
// Internal clock, no PLL, etc.
HAL_RCC_DeInit();
// Disable SysTick timer and reset it to default values
SysTick->CTRL = 0;
SysTick->LOAD = 0;
SysTick->VAL = 0;
// Disable all interrupts
__disable_irq();
// Remap system memory to address 0x0000 0000 in address space
__HAL_SYSCFG_REMAPMEMORY_SYSTEMFLASH();
// Set jump memory location for system memory
// Use address with 4 bytes offset which specifies jump location where program starts
SysMemBootJump = (void (*)(void)) (*((uint32_t *)(addr + 4)));
/**
* Set main stack pointer.
* This step must be done last otherwise local variables in this function
* don't have proper value since stack pointer is located on different position
*
* Set direct address location which specifies stack pointer in SRAM location
*/
__set_MSP(*(uint32_t *)addr);
/**
* Call our function to jump to set location
* This will start system memory execution
*/
SysMemBootJump();
}
}However, in this new application, I require to use the USB interface for flashing the firmware. This application implements a USB CDC, so I modified the above code as follows:
void Bootloader_Start(uint32_t run) {
void (*SysMemBootJump)(void);
/**
* Set system memory address.
*
* For STM32F072, system memory is on 0x1FFF C800
* For other families, check AN2606 document table 155 with descriptions of memory addresses
*/
volatile uint32_t addr = 0x1FFFC800;
if (run == TRUE)
{
// De-initialize all peripherals configured for this Application
HAL_TIM_Base_DeInit(&htim6);
HAL_TIM_Base_DeInit(&htim7);
USBD_DeInit(&hUsbDeviceFS);
// Disable RCC, set it to default (after reset) settings
// Internal clock, no PLL, etc.
HAL_RCC_DeInit();
// Disable SysTick timer and reset it to default values
SysTick->CTRL = 0;
SysTick->LOAD = 0;
SysTick->VAL = 0;
// Disable all interrupts
__disable_irq();
// Remap system memory to address 0x0000 0000 in address space
__HAL_SYSCFG_REMAPMEMORY_SYSTEMFLASH();
// Set jump memory location for system memory
// Use address with 4 bytes offset which specifies jump location where program starts
SysMemBootJump = (void (*)(void)) (*((uint32_t *)(addr + 4)));
/**
* Set main stack pointer.
* This step must be done last otherwise local variables in this function
* don't have proper value since stack pointer is located on different position
*
* Set direct address location which specifies stack pointer in SRAM location
*/
__set_MSP(*(uint32_t *)addr);
/**
* Call our function to jump to set location
* This will start system memory execution
*/
SysMemBootJump();
}
}When running this function microcontroller does disconnect from the computer, but it never loads the DFU, and the computer shows unknown device, so I am not able to see it listed on the SMT32CubeProgrammer.
Am I missing something?
Thanks in advance for your support.