WIZnet Developer Forum

No Miso response when trying to read register

Hi, I am trying to read the W5500 version register to make sure I have set up the HW properly. I am sending out 0x00 0x39 0x00 0x5F and reading the MISO bytes. I receive MISO signals randomly. I send out my command every 500ms and never really see any MISO signals when probed

Here is our design to double check:

Will upload some screenshots of scope data in the morning if there is nothing obvious I am doing wrong


Tested CLK, MOSI and CS all on the Wiznet W5500 pins and they are all getting to the chip, just no MISO signals are being sent back at all

If I wait till CS line is pulled high before powering the Wiznet chip I get very occasional MISO data. I am sending the read command and get these 4 lots of 4 bytes randomly, maybe every 10-20 seconds:

Same values everytime it does happen

Update: The XI side of my crystal is not oscillating. I get 25MHz on the Xo side but not XI. That would explain why it is not working I guess

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