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Visitor II
December 16, 2020
Solved

Custom HID issue : offset in hid data

  • December 16, 2020
  • 4 replies
  • 992 views

Hi,

I am working on Nucleo STM32H743ZI

I am using a 64byte size custom usb hid when I send my data frames i get an offset of 6 zeros as shown here :

0693W000006FwU8QAK.pngAny ideas where it comes from ?

Regards,

Gabriel

    This topic has been closed for replies.
    Best answer by Ons KOOLI

    Hi GTéta.1,

    When working with DMA in H7 products you should pay attention on where you put your code.

    By default in the linker file, you can see that the RAM starts from 0x20000000 address and ends in 0x2001FFFF which is the DTCM region.

    Unfortunately, the DTCM is not accessible by DMA. Therefore, When working with DMA, you should put your code in an accessible region by DMA (for example AXI SRAM).

    Please refer to the RM0433 for more details.

    Best Regards,

    Ons.

    4 replies

    Gabriel TAuthor
    Visitor II
    December 16, 2020

    Update :

    The problem disappear if i disable usb dma :

    0693W000006FzgbQAC.png

    Gabriel TAuthor
    Visitor II
    December 16, 2020

    I would like to use DMA, anyparameter I am missing for the USB DMA ?

    Ons KOOLIAnswer
    Visitor II
    December 16, 2020

    Hi GTéta.1,

    When working with DMA in H7 products you should pay attention on where you put your code.

    By default in the linker file, you can see that the RAM starts from 0x20000000 address and ends in 0x2001FFFF which is the DTCM region.

    Unfortunately, the DTCM is not accessible by DMA. Therefore, When working with DMA, you should put your code in an accessible region by DMA (for example AXI SRAM).

    Please refer to the RM0433 for more details.

    Best Regards,

    Ons.

    Visitor II
    December 17, 2020

    Hi GTéta.1,

    In case your problem is solved, please mark this question as answered by selecting the best answer.

    Best Regards,

    Ons.