The data sheet 6.3.10 only gives the Flash memory timings, not the FLASH peripheral SR and CR register timings. The reference manual includes the code snippet below in A.2.3 but when I try it the SR says the erase is done immediately.
/* (1) Set the PER bit in the FLASH_CR register to enable page erasing */
/* (2) Program the FLASH_AR register to select a page to erase */
/* (3) Set the STRT bit in the FLASH_CR register to start the erasing */
/* (4) Wait until the BSY bit is reset in the FLASH_SR register */
/* (5) Check the EOP flag in the FLASH_SR register */
/* (6) Clear EOP flag by software by writing EOP at 1 */
/* (7) Reset the PER Bit to disable the page erase */
FLASH->CR |= FLASH_CR_PER; /* (1) */
FLASH->AR = page_addr; /* (2) */
FLASH->CR |= FLASH_CR_STRT; /* (3) */
while ((FLASH->SR & FLASH_SR_BSY) != 0) /* (4) */
{
/* For robust implementation, add here time-out management */
}
if ((FLASH->SR & FLASH_SR_EOP) != 0) /* (5) */
{
FLASH->SR = FLASH_SR_EOP; /* (6)*/
}
else
{
/* Manage the error cases */
}
FLASH->CR &= ~FLASH_CR_PER; /* (7) */
