Flash Memory program

[ajimathew]

Dear @KDJEM.1 

when I read the manual "rm0432" It is given that

The Flash memory programming sequence in standard mode is as follows:

1. Check that no Flash main memory operation is ongoing by checking the BSY bit in the
Flash status register (FLASH_SR).
2. Check and clear all error programming flags due to a previous programming. If not,
PGSERR is set.
3. Set the PG bit in the Flash control register (FLASH_CR).
4. Perform the data write operation at the desired memory address, inside main memory
block or OTP area. Only double word can be programmed.
– Write a first word in an address aligned with double word
– Write the second word
5. Wait until the BSY bit is cleared in the FLASH_SR register.
6. Check that EOP flag is set in the FLASH_SR register (meaning that the programming
operation has succeed), and clear it by software.
7. Clear the PG bit in the FLASH_SR register if there no more programming request
anymore.

My code is

uint64_t data=0x1234567890ABCDEF;

HAL_FLASH_Unlock();
HAL_FLASH_Program(FLASH_TYPEPROGRAM_DOUBLEWORD,0x0803F000,data);
HAL_FLASH_Lock();

The data have been stored in the desired address. My doubt is, as per the manual I didn't set PG bit and check any status of the flash register but I got an output how?

[KDJEM.1 · Accepted solution]

Hello @ajimathew ,

You have already set the PG bit.

Because when you are calling HAL_FLASH_Program(FLASH_TYPEPROGRAM_DOUBLEWORD,0x0803F000,data); the PG has been set. 

static void FLASH_Program_DoubleWord(uint32_t Address, uint64_t Data)
{
  /* Check the parameters */
  assert_param(IS_FLASH_PROGRAM_ADDRESS(Address));

  /* Set PG bit */
  SET_BIT(FLASH->CR, FLASH_CR_PG);

  /* Program first word */
  *(__IO uint32_t*)Address = (uint32_t)Data;

  /* Barrier to ensure programming is performed in 2 steps, in right order
    (independently of compiler optimization behavior) */
  __ISB();

  /* Program second word */
  *(__IO uint32_t*)(Address+4U) = (uint32_t)(Data >> 32);
}​

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Kaouthar