title: stm32 ETH_IRQHandler never hit
body: <p>Im using stm32f746ZGT + LAN8472A  and lwip + freertos on my custom board. I generated default ethernet project by cubemx. I set static ip.</p>
  
  <ol>
  <li>After connect the cable Link leds seem like good. Yellow one is
  stable and green one is blinky.</li>
  <li>In debugging i can see netif is fully configured and link is up.</li>
  <li>RXD0 and RXD1 pins which are entering mcu have signal (i can see on
  oscilloscope screen).</li>
  <li>Clocks are good (i tested with oscilloscope).</li>
  </ol>
  
  <p>But ETH_IRQHandler never hit so it doesnt answer any questions such as ping request. (I enabled ICMP at lwIP settings). What should i check to find the source of problem</p>