Help with LAN8720

ESPHome
1

Hi, I have 2 LAN8720 modules and cannot get either working.

I have been through posts online regarding this module, including the resistor modification but I cant seem to get anything to work, the unit negotiates with the switch and appears to be all good, but there is no network access, I cannot ping it at all.

My YAML is below,

ethernet:
  type: LAN8720
  mdc_pin: GPIO23
  mdio_pin: GPIO18
  clk_mode: GPIO0_OUT
  phy_addr: 1
2

Which esp board are you using? If you wired it yourself show us what you did.

3

https://docs.espressif.com/projects/esp-idf/en/stable/esp32/hw-reference/esp32/get-started-ethernet-kit.html#ip101gri-phy-interface

4

Have you got a picture?

5

Not with me right now,

But I did the resistor modification, as per this image, this is my exact board.

image
image1200×900 110 KB

Not sure what other pins I need, but I only have the following connected.

TXD1
RXD1
TXD0
RXD0
MDIO
MDC
REF_CLK

6

How are they connected to the esp32?

I assumed you had read the docs

If your Ethernet board is not designed with an ESP32 built in, it’s common to attempt to use flying leads, dupont wires, etc. to connect the Ethernet controller to the ESP32. This approach is likely to fail, however, as the Ethernet interface uses a high frequency clock signal that will not travel reliably over these types of connections. For more information and wiring details refer to the link in the See also section.

7

Hmmm yea I did see this,

However I also have seen multiple posts of people using Dupont wires, I have however, soldered my Dupont jumpers onto the pins for a more solid connection.

I would expect to see inconsistencies in ping responses and response times etc., rather then just no reply at all, I have not had 1 ping response from this board.

Not sure if I need this but see no mention of it from anyone, anywhere.

power_pin: GPIO5

8

In the docs

power_pin (Optional, Pin Schema): The pin controlling the power/reset status of the Ethernet controller. Leave unspecified for no power pin (default).

9

Yea still no luck with this :frowning:

10

I’ve been using the LAN8720 module recently as well. The module comes in three versions: one with a 50MHz crystal, one with a 25MHz crystal, and one without a crystal. When using an external oscillator, IO0 must be used as the input. To prevent IO0 from being pulled down by the crystal, the power-en feature is used to ensure that IO0 can be pulled high (in some examples, IO0 is pulled up). The board you have uses the version without a crystal, so you don’t need to consider the power configuration.