Question
STM32F042K6 - Jump to Bootloader
Hello everyone,
I have an STM32F042K6 running a small application in a hard-to-reach enclosure. I want to use the USB interface for firmware updates. This interface is used for sending data. The bootloader is activated by a long button press. I already have this code running on an STM32F303, and it works great. Unfortunately, it doesn't work on the F042.
I changed the addr to "0x1FFFC400" for the F042K6.
I changed the addr to "0x1FFFC400" for the F042K6.
void JumpToBootloader(void) {
void (*SysMemBootJump)(void);
/**
* Step: Set system memory address.
* For STM32F303, system memory is on 0x1FFFD800
* For other families, check AN2606 document table 110 with descriptions of memory addresses
*/
volatile uint32_t addr = 0x1FFFD800;
/**
* Step: Disable RCC, set it to default (after reset) settings
* Internal clock, no PLL, etc.
*/
//MX_USB_DEVICE_DeInit();
HAL_RCC_DeInit();
/**
* Step: Disable systick timer and reset it to default values
*/
SysTick->CTRL = 0;
SysTick->LOAD = 0;
SysTick->VAL = 0;
/**
* Step: Disable all interrupts
*/
//__disable_irq();
/**
* Step: Remap system memory to address 0x0000 0000 in address space
* For each family registers may be different.
* Check reference manual for each family.
*
* For STM32F4xx, MEMRMP register in SYSCFG is used (bits[1:0])
* For STM32F0xx, CFGR1 register in SYSCFG is used (bits[1:0])
* For others, check family reference manual
*/
__HAL_SYSCFG_REMAPMEMORY_SYSTEMFLASH(); //Call HAL macro to do this for you
/**
* Step: 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)));
/**
* Step: 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);
/**
* Step: Actually call our function to jump to set location
* This will start system memory execution
*/
SysMemBootJump();
/**
* Step: Connect USB<->UART converter to dedicated USART pins and test
* and test with bootloader works with STM32 Flash Loader Demonstrator software
*/
}
I then looked for alternative solutions, but they also don't work, and I am at a loss.
Example:
I disabled the BOOT_SEL Bit for the second attempt.
The goal is to use the STM32CubeProgrammer to upload new firmware.
What else could I do?
Thanks!
Greetings
Paul