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Visitor II
August 2, 2025
Solved

STM32F7xx Family Undocumented QSPI Hardware Bug

  • August 2, 2025
  • 3 replies
  • 642 views

Peripheral: QSPI

Bug: Bit 4 of FTHRES[4:0] in the Control Register is not set when written with threshold values in the range

0x10 - 0x1F. Works fine for threshold values in the range 0x00 - 0x0F. So, for example, if one writes 0x16 for a

threshold level of 23-bytes, the actual value is 0x06 corresponding to a threshold level of 7-bytes.

Encountered on: STM32F723IE, STM32F746NG and STM32F767ZI

Comments: Checked the errata data sheets for the above processors and there is no mention of the bug.

Request: Please can anyone confirm that this is indeed an undocumented hardware bug.

    This topic has been closed for replies.
    Best answer by KDJEM.1

    Hello @psymo000 ,

     

    I apologize for my late reply and thank you for bringing this issue to our attention.

    I confirm the issue. This behavior will be documented in the errata sheets for the impacted products.

     

    Internal ticket number: 215366 (This is an internal tracking number and is not accessible or usable by customers).

    Thank you.

    Kaouthar

    3 replies

    Technical Moderator
    August 5, 2025

    Hello @psymo000;

     

    Thank you for bringing this issue to our attention.

    I will check internally and get back to you as soon as possible.

     

    Thank you.

    Kaouthar

    psymo000Author
    Visitor II
    September 3, 2025

    This bug extends to the STM32F4 family of devices that support QSPI. Checked on a Nucleo-F446ZE board and encountered the bug. Again checked the errata data sheet for the device and there was no mention of the bug. This being the case, both STM32F Cortex-M4 and -M7 devices that support QSPI obviously use the same silicon IP for the peripheral.

    It has been just over 1 month since the original post and I am stilling waiting for confirmation. Not impressed with the level of professionalism shown by STMicroelectronics with regards this matter. A very poor reflection on the company.

    KDJEM.1Answer
    Technical Moderator
    September 3, 2025

    Hello @psymo000 ,

     

    I apologize for my late reply and thank you for bringing this issue to our attention.

    I confirm the issue. This behavior will be documented in the errata sheets for the impacted products.

     

    Internal ticket number: 215366 (This is an internal tracking number and is not accessible or usable by customers).

    Thank you.

    Kaouthar

    psymo000Author
    Visitor II
    September 6, 2025

    Thank you for the confirmation.