NUCLEO-F767ZI dead Ethernet, no active line LED's :: SOLVED

[Joerg Wagner]

Hello.

I cannot use Ethernet with my 2 weeks old NUCLEO-F767ZI (chip version Z).

Probably the LAN8742A does not work properly anymore.

After initilization I perform a check:

if (HAL_ETH_ReadPHYRegister(&heth, PHY_BSR, &regvalue)==HAL_OK) {
  if (regvalue&0x04) {
     // cable connected, but with this board never reached
    ...
  }
}

No LED of the connector is active.

The software works on other boards. (Latest FW, etc.)

Is there a chance to rescue the board?

Thank you Joerg

[Piranha]

https://community.st.com/s/question/0D50X0000BiCXYbSQO/stm32f767zi-project-will-run-at-100mbit-ethernet-but-not-10mbit

Check if your code has the same problem. Is your code based on CubeMX or ST's examples?

It seems that this is another bug to add to my already long list of network related bugs:

https://community.st.com/s/question/0D50X0000BOtfhnSQB/how-to-make-ethernet-and-lwip-working-on-stm32

[Piranha]

It's written in the description - yes, but not from ST. Except for register definition headers, there is no code from ST...

[Joerg Wagner]

CubeMX.

I remember that you do not provide your source code. What a shame.

[Joerg Wagner]

Hello. I just tried your demo firmware again on the board with the problems described above.

Five days ago I made a test and it worked. I wanted to measure the elapsed time when ETH is ready.

But now no LED's of the connector are on and network is not active.

Here is the serial output:

.[2J.[HNUCLEO-144: ARM Cortex-M7 r1p0 216 MHz, Flash 2048 KB

.[2K.[G5,526 [HTTP] Server created

.[2K.[G8,602 [Iperf2] Server created

.[2K.[G11,895 [main] Starting OS scheduler...

.[2K.[G0:00:00,000 [ETH] Task started

[Piranha]

> But now no LED's of the connector are on and network is not active.

As on this board the Ethernet connector LEDs are connected to PHY chip and PHY has it's own quartz crystal, it works absolutely autonomously. I even checked this by mass erasing the MCU and power cycling the board. The PHY still works and LEDs turn on after auto-negotiation finishes after approximately 2 seconds.

Check the quality of crimped connectors, if there are such. Try other cable, switch/router, power supply for it. Check if the Nucleo isn't physically damaged, especially the Ethernet connector.

P.S. Serial output looks strange because your terminal client doesn't understand VT100 terminal protocol, which is the de facto standard. On Windows I suggest Tera Term as one of the best terminals. PuTTY is also a neat tool.

[Joerg Wagner]

Hi. I work with Mac, no Tera Term available.

Tested several cables and checked the connector under glasses.

Sometimes it works sometimes not. All cables work fine with other

devices. Something is strange with the NUCLEO-F767ZI board and

I cannot use it in production at a customer. Goes into trash.

[Pavel A.]

Hi Joerg, @Joerg Wagner​ ,

Could you share how you derive MAC address from the board ID?

IIRC only some bytes or bits in the board ID are unique, and ST does not document which bits are unique for H7. Again, IIRC.

-- Pavel

[Joerg Wagner]

Hi Pavel. Yes sure: 00:80:E1:45:00:45

[Joerg Wagner]

Hi. Sometimes the yellow LED flashes once for approx. 100ms after startup, but very rare.

Your software does not akquire an IP address via DHCP properly, regardless if the

LED's are on sometimes. After powering up sometimes the LED's are on, but after a

soft reset (sending break via Terminal) the LED's will never turned on.

[Pavel A.]

@Joerg Seriously... given the 3 * 32 bits of the MCU ID, how do you generate 6 bytes of MAC address (except of few special bits) ?

-- pa