Unable to get DHCP working with STM32F407 + DP83848

[PFirm.1]

Hi, I am unable to get DHCP working. I am using the DP83848 board with an STM32F4 Discovery board. I am using the STM32CubeIDE and so had the code generated, the DP83848 is working on RMII mode.

When I enable or disable DHCP and connect it to my PC/laptop it would read an IP address of 169.254.***.*** of some sort with a MAC address of 00:e0:4c:68:01:a8 when it should be 00:80:E1:00:00:00 according to the configurations I can see in the IOC for the project. Anyone know why this is? Thanks in advance

[LCE]

What you see is probably not the discovery board.

I think you might need an extra software application that can make your PC / laptop work as an DHCP server. I used "dhcpsrv" some time ago.

[PFirm.1]

Hi LCE,

I think it is the discovery board as when I ping it while connected, it is able to ping it correctly but as soon as I plug it off it is unable to ping it anymore like in the screenshot attached. But I will try to get my laptop working as a DHCP server first. Any other suggestions? Thanks

[Pavel A.]

Address like 169.254.x.y is APIPA address.

Check if your LwIP options file enables APIPA.

[Imen.D]

Hello @PFirm.1​ ,

Would it be possible to share your initialization/configuration? It may be a problem with the connection!

Did you control the nRST pin?

Imen

[PFirm.1]

Hi Imen,

Attached is the ioc for the project you can open with Cube. No I did not control the nRST pin. I have read in this thread that for the H7, someone had this problem because the DMA descriptor addresses are initialized by Cube incorrectly. Might this be a problem for this project as well? If so, how could I fix it.

[waclawek.jan]

169.254.x.y is consequence of AUTOIP being enabled in lwipopts.h

http://www.nongnu.org/lwip/2_0_x/group__lwip__opts__autoip.html

Check if you have DHCP enabled, if dhcp_start() is called for the ETH netif, observe the netif's dhcp struct values, observe on bus if your device sends DHCP_REQUEST broadcasts... i.e. debug as usually.

JW