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Visitor II
March 27, 2025
Solved

DHCP error in LwIP Ethernet middleware on STM32H755 CM4

  • March 27, 2025
  • 2 replies
  • 755 views

The problem ethernet link with NUCLEO-H755ZI-Q.
The conditions are as follows:

  • Board: NUCLEO-H755ZI-Q
  • Ethenet select core: CM4
  • STM32Cube_FW_H7: V1.12.1
  • LWIP: V2.1.2
  • DHCP client

In this case, the Ack from the DHCP server could not be confirmed as being received.
dhcp->pcb_allocated is set to 0 (in function of dhcp_recv()).
A similar error has not occurred with CM7.

Do you happen to know the reason for this?

    This topic has been closed for replies.
    Best answer by mƎALLEm

    @MasatoKawatsuma wrote:

    The above thread mentions MPU, but I don't use MPU in my environment.
    ・RTOS disabled
    ・MPU not used

     

     No the problem in that thread is not only about the MPU configuration but also linked to the memory partition.

    So check also your SRAM memory partitioning.

    2 replies

    Technical Moderator
    March 27, 2025

    Hello @MasatoKawatsuma and welcome to the community,

    Related question raised on this thread.

    Visitor II
    March 28, 2025

    The above thread mentions MPU, but I don't use MPU in my environment.
    ・RTOS disabled
    ・MPU not used

     

    Also, the following warning occurred while debugging dhcp, so I think it might be a problem with pbuf memory management.

    Assertion "pbuf_free: p->ref > 0" failed at line 753 in {path}/Middlewares/Third_Party/LwIP/src/core/pbuf.c

    If you know anything, please let me know.

    mƎALLEmAnswer
    Technical Moderator
    March 28, 2025

    @MasatoKawatsuma wrote:

    The above thread mentions MPU, but I don't use MPU in my environment.
    ・RTOS disabled
    ・MPU not used

     

     No the problem in that thread is not only about the MPU configuration but also linked to the memory partition.

    So check also your SRAM memory partitioning.

    ST Employee
    March 27, 2025

    Hi @MasatoKawatsuma 

     

    This post has been escalated to the ST Online Support Team for additional assistance.  We'll contact you directly.

     

    Regards,

    Billy