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unable to ping Ethernet with STM32F207 board , LAN8742A and LWIP

Associate II

I'm trying to build a server using STM32F207 processor and LAN8742A I have used CubeIDE to generate the configuration code and modified as follows:

1) ETH -> Auto negotiation Enabled

            -> PHY Address = 0

            -> PHY SR Offset = 1F

            -> PHY Speed Mask = 0x0004

             -> PHY Duplex Mask = 0x0010

             -> PHY Interrupt Source Flag register Offset = 0x001D

             -> PHY Link Down Interrupt = 0x0010

Rest of the settings are default. Since I found these to be wrongly auto generated.

2) LWIP ->  LWIP_DHCP = Disabled

               -> IP Address =

               -> Netmask Address =

               -> Gateway Address =

3) LWIP -> Key Options -> MEM_SIZE (Heap Memory Size) = 10*1024 Bytes

Then generated the code and added the below  

int main(void)


  while (1)a

But unable to ping the above IP address from my command prompt. when I check "Ipconfig" on the command prompt, it shows this  
Autoconfiguration IPv4 Address. . :
Subnet Mask . . . . . . . . . . . :
Default Gateway . . . . . . . . . :
I have cross verified it shows the above only when I connect LAN cable to my board. But doesn't show my IP Address which I configured.

The Processor is able to communicate with PHY , I could check on my Oscilloscope, the data sent is correct via MDIO and MDC. If I can establish this ping, then I have to create a TCP Server using my board to transfer sensor data to pc and receive command from PC.

 Please Help me through , what am I doing wrong or if there are any bugs in the STM32 libraries etc.

ST Employee

Hello @joseph787 ,

are you using a costume board or this is the nucleo board ?

i think you shoud check the PHY and try to make sure it is configured correctly maybe try to get the status of the LAN8742_Init() function .

or try reading the device address from special mode register .

i recommend you debug in step by set inside the LAN8742_Init() to make sure you have the right configuration set .




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