Arty Board unable to receive response from Ethernet PHY

[sreehari]

Hi,

 I am able to run ethernetlite example code (internal loopback) available in Xilinx SDK. Hardware platform I used was echo server one.

I tried to do a simple mdio read to read the PHY registers using following function 

XEmacLite_PhyRead () , Physical address set as 1... Using scope i probed mdio line (R173) and i could see activity for the initial write but when the read section line remains high....Thus returning 0xffffh.... 

PHY reset is held high (R183)

I tried scanning the entire address range available for PHY but no response. Every time the register content is the same  0xffffh.

/****

for(reg_count=0;reg_count<32;reg_count++)
{
    Status=XEmacLite_PhyRead (EmacLiteInstPtr,reg_count,3,&RegContent);
    if (Status != XST_SUCCESS) {
        return XST_FAILURE;
    }
    if(RegContent!=0xffff)
    {
        break;
    }

******/

Why does my PHY not respond to MDIO commands??.... Am I missing something...please Help

 

[D@n]

When you probed the wires, did you probe the clock line as well?

Dan

[jpeyron]

Hi @sreehari,

Welcome to the Digilent Forums!

As of yet I haven't used the LWiP with MDIO commands. Here is a forum thread that discusses MDIO with the Arty ethernet using linux and Here is a non-digilent forum thread that might be helpful.

best regards,

Jon