解锁

void flash_unlock(void)
{
  /* (1) Wait till no operation is on going */
  /* (2) Check if the PELOCK is unlocked */
  /* (3) Perform unlock sequence */
  while ((FLASH->SR & FLASH_SR_BSY) != 0) /* (1) */
  {
  /* For robust implementation, add here time-out management */
  }
  if ((FLASH->PECR & FLASH_PECR_PELOCK) != 0) /* (2) */
  {
   FLASH->OPTKEYR = 0xFBEAD9C8;
   FLASH->OPTKEYR = 0x24252627;
   FLASH->PEKEYR = 0x89ABCDEFU;
   FLASH->PEKEYR = 0x02030405U;
  }
  FLASH->PRGKEYR = 0x8C9DAEBF;
  FLASH->PRGKEYR = 0x13141516;
}

擦除，这个芯片每页是128字节，别当成256

void flash_erase(void)
{
 uint32_t addr = 0;

  /* 解锁flash */
  __disable_irq();
  flash_unlock();

  /* 擦除对应扇区 */
  for(addr = UPDATE_ADDR; addr < END_ADDR; addr += 128)
  {
    FLASH->PECR |= FLASH_PECR_ERASE | FLASH_PECR_PROG; /* (1) */
   *(__IO uint32_t *)addr = (uint32_t)0; /* (2) */
   while ((FLASH->SR & FLASH_SR_BSY) != 0) /* (3) */
   {
   /* For robust implementation, add here time-out management */
   }
   if ((FLASH->SR & FLASH_SR_EOP) != 0) /* (4) */
   {
   FLASH->SR = FLASH_SR_EOP; /* (5) */
   }
   else
   {
   /* Manage the error cases */
   }
   FLASH->PECR &= ~(FLASH_PECR_ERASE | FLASH_PECR_PROG); /* (6) */
  }

  /* 加锁flash */
  while ((FLASH->SR & FLASH_SR_BSY) != 0) /* (1) */
  {
   /* For robust implementation, add here time-out management */
  }
  FLASH->PECR |= FLASH_PECR_PELOCK; /* (2) */
  __enable_irq();
}

写Flash

void flash_write(uint32_t addr, uint8_t* data, uint16_t len)
{
  uint32_t old_addr = addr;
  uint32_t i = 0;

  __disable_irq();
  flash_unlock();

  /* 写数据 */
  while(1)
  {
    /* (1) Perform the data write (32-bit word) at the desired address */
    /* (2) Wait until the BSY bit is reset in the FLASH_SR register */
    /* (3) Check the EOP flag in the FLASH_SR register */
    /* (4) clear it by software by writing it at 1 */
    *(__IO uint32_t*)(addr + UPDATE_ADDR + i) = ((uint32_t)data[i+3]<<24)+((uint32_t)data[i+2]<<16)+((uint32_t)data[i+1]<<8)+((uint32_t)data[0]);
    while ((FLASH->SR & FLASH_SR_BSY) != 0) /* (2) */
    {
     /* For robust implementation, add here time-out management */
    }
    if ((FLASH->SR & FLASH_SR_EOP) != 0) /* (3) */
    {
     FLASH->SR = FLASH_SR_EOP; /* (4) */
    }
    LL_mDelay(1);
    i+=4;
    if(i>=len)
    {
      break;
    }
  }
  /* 加锁flash */
  while ((FLASH->SR & FLASH_SR_BSY) != 0) /* (1) */
  {
   /* For robust implementation, add here time-out management */
  }
  FLASH->PECR |= FLASH_PECR_PELOCK; /* (2) */

  flash_test_read(old_addr);
  __enable_irq();
}

STM32L031写Flash不使用HAL库_单片机