W5500 SPI not response

agent47 · January 24, 2021, 11:38am

Hi there,

I have integrated the W5500 into my own circuit with an ESP32 microcontroller.
I have largely adopted the circuit from the Wiki. Now I have the problem that the chip on the finished PCB does not respond to requests on the SPI bus.
I suspect there is still a problem with the circuit, but I have no idea where to look.

At the moment I’m not sure whether I have used the correct inductor.

Can someone give me some help?

reference: products:w5500:refschematic [Document Wiki]

agent47 · January 30, 2021, 10:42am

In the meantime I have replaced the L1 with a ferrite with 120 ohms at 100 MHz (BLM21PG121SN1D).
But that didn’t help.

In my circuit diagram, the yellow LED is also connected the wrong way round, but that shouldn’t be a problem for the time being.

When I plug in a network cable, the green LED flashes irregularly. So, at least on the network connection side, everything seems to fit.

At the VBG pin (18) I can also measure the 1.2V which should also be present according to the data sheet.

I still have the problem that I don’t get any answers from the W5500 chip on the SPI bus.
Does nobody have an idea why that could be?

Scott · February 1, 2021, 5:53am

Dear @agent47

There doesn’t seem to be a big problem with your circuit.

You have both SPI and Ethernet not working?

Basically, you should check if 25MHz is working.

For SPI, first check the connection with your MCU.

For Ethernet, check out our Design Guide.

https://wizwiki.net/wiki/doku.php/design_guide:hardware:start

Thank you.