K64 ethernet fails in 144pin device

[petertsipouras]

Hello,

back in 2017 I had posted a tcpecho project using FRDM64F with SDK1.3 , Processor expert and FreeRTOS. 

The original post is at Problem with Tcp_echo and PE 

Recently I have a hardware design with the same K64F chip but in the 144pin LQFP package.

I have tried to use the tcpecho, with only a few pin number modifications, to validate the hardware.

It does not work even though all signals tied to the KSZ8081RNA  PHY match those on the FRDM64F and the reset is  the same 100msec time constant ramp.

The 50Mhz clock from the 8081 is tied to pin 72.

The only difference I see is that the FRDM  pin MDIO stays high after reset, whereas the 144pin design shows the MDIO briefly active after reset.

Has anyone seen this type of behavior? I am attaching both projects with much appreciation for any advice.

[Sabina_Bruce]

Hello Peter,

My name is Sabina and I'll be happy to help you find the root cause of this issue. Unfortunately I do not have a 144 pin K64 so I will not be able to test this with you. If you could please share your schematic I would appreciate it so I can verify the connections and check it with detail. Also could you please confirm the version of the SDK you are currently using with the 144 pin package.

Best Regards,

Sabina

[petertsipouras]

Hi Sabina

Sorry for the delay, but I accidentally found the cause. It was simply a short to GND if the negative transmit output line. Its trace was very close to a ground pad and not visible because it was underneath the Magjack. Now the echo works fine :>)

Best regards

Pete