ESP32-EVB: Ethernet Connection pysically lost

Started by A002005, February 25, 2022, 05:04:49 PM

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I can think of something else to add. Regarding the EMC issue, I put some aluminum foil around the Olimex (BSB-LAN) and also around the bus line that goes from the BSB-LAN to control the heating as a shield. I think I can observe that things got slightly better with the cancellations. But I will soon be using a shielded CAT 8 cable for the bus line and the Olimex EVB from the heater a little further away. Let's see...
To illustrate this, I'm attaching a picture where you can see the installation situation. Unfortunately, I don't have a more recent picture at the moment where you can see my temporary solution with the aluminum foil. Many greetings Jürgen

Link to Picture:


I don't see where is the Ethernet connected, also where are the two wires that go between ESP32-EVB and the boiler controller connected (regarding ESP32-EVB)?
Technical support and documentation manager at Olimex


What is your Ethernet code did you add delay during initialization?
Technical support and documentation manager at Olimex


Hello Jürgen,
I have same problems with the similar setup (ESP32-EVB Rev K1 with current BSB-LAN).
The ethernet connection is lost every 8-9 seconds (my thread is located in the microcontrollers/ESP32 section).

Just a questions to check possible differences (or even similarity):
Will your board also loose ethernet connectivity without external (Bus/USB) connections?
Thats what i see with a second EVB board, just running with the same code (BSB-LAN).
Just power (via power supply) and ethernet, nothing else connected, even no usb port.
Power up, ethernet link comes up and drops down after 10 seconds, again and again.

And secondly: Are there any differences by powering the board with USB or power jack?
My board is only running stable when USB powered, the loss of ethernet is present with external power supply only.

The backend BSB-LAN code is running fine. All paramaters are logged from the external bus and will be stored on SD card as well.
It is just switching ethernet on/off periodically, so I am using it only on boot for NTP time adjustment.
If it is powered off and re-powered over USB, all LAN connections are stable.


So now I can report something good.
After my last attempt at BSB-LAN on Olimex-EVB, connected directly to the laptop via LAN cable, also resulted in a crash, I removed the Olimex-EVB from the heater and installed it about 1m further outside.
And lo and behold, not a single abortion for 2 days.
So it's probably the burner start that triggers a magnetic wave and influences the Olimex EVB. I don't understand why this has an effect on LAN and not on WLAN.
In any case, it's a shame for everyone involved for the many empty kilometers.


LAN uses an extra chip LAN8710A and wires running around the board between the connector, the main ESP32 chip, the LAN8710A chip (and each wire acts as antenna for picking up noise) so it sounds reasonable to be more susceptible to the noise from triggering the load. In comparison WIFI is all inside the ESP32 module.
Technical support and documentation manager at Olimex