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Flash memory frequency using QSPI is too slow.


The stm32h747 controls Flash memory using qspi.

Flash is using mt25ql256.

Write and Read actions have been confirmed.

But the frequency doesn't come out like a data sheet in flash memory.

The speed of the QSPI clock is around 1.25Mhz.
QSPI  ClockPrescaler  : 2



The frequency does not come out like a flash memory data sheet.


I want to know what the problem is, please help me!!


Unpack the clocks as the MCU sees them.

  printf("\n\nCore=%d, %d MHz\n", SystemCoreClock, SystemCoreClock / 1000000);
  printf("HCLK=%d\n", HAL_RCC_GetHCLKFreq());
  printf("APB1=%d\n", HAL_RCC_GetPCLK1Freq());
  printf("APB2=%d\n", HAL_RCC_GetPCLK2Freq());

Likely not running with the bus clocks you think it is.

Check the clock initialization code doesn't fail, either HSE or PLL failing to come ready would be my guess.

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