WIZnet Developer Forum

Arduino and w5500

Hi guys,
I want to interface Arduino UNO with the w5500 evaluation board. I’ve only one problem: when I plug the Arduino UNO SPI wires (the SCLK wire in the specific) on the w5500 I can see from the serial (TeraTerm) that,even with a blank sketch running on the Arduino UNO, the IP,Gateway,DNS,MAC and port are reset to 0. If the Arduino UNO is unplugged all the parameters are assigned correctly. It clearly seems an hardware pinning related problem, I checked 20 times the pinning and the electrical continuity between cables.
The project is really similar to the Arduino ethernet shield, the evaluation board is shield compatible, so the ports that I’m using are 10(SS),11(MOSI),12(MISO),12(SCLK), GND. Any suggestion, why is resetting?
Thanks!

Hi,

What did you mean unplugged??
Disconnection between W5500 and UNO?? or UNO and power cable?? or else??

Did you write and read other registers??
Did it have no problem??

if the UNO is not running a sketch i would assume all pins are input by default and should not affect the hardware …(i’m not an arduino user so not sure, but this would be the case with a PIC) but even if your pins where outputs and driving the SPI pins i still don’t see how that would bring down your mac and ip address etc… anyway just to be sure, use a resistor and LED and confirm your UNO is neither sinking nor sourcing a current… specially confirm your uno is not sinking current… most of my classmates forget 0V is still an output!!

Dear coffeecupnz,

In your hardware (Arduino UNO + W5500EVB),
Arduino UNO could not access W5500 in W5500EVB.

  1. SCS_N(chip select) of W5500 does not connect to D10 in Arduino pin-header.
    Please, check SCS_N signal as below pictures.
  2. W5500EVB has Cortex M0 MCU (Host MCU) and W5500. So, it is not Ethernet shield is just arduino pin-header compatible
  3. Ethernet shield by using W5500 is ioShield-A. Refer to URL; wizwiki.net/wiki/doku.php?id=osh … ld-a:start

Thanks,

[quote=“hjjeon0608”]Hi,

What did you mean unplugged??
Disconnection between W5500 and UNO?? or UNO and power cable?? or else??

Did you write and read other registers??
Did it have no problem??[/quote]

For Unplugged I mean disconnected from the board, and also when UNO is not powered.
I compiled a blank sketch with SPI.h included, so the ports are set properly.

[quote]
but even if your pins where outputs and driving the SPI pins i still don’t see how that would bring down your mac and ip address etc… anyway just to be sure, use a resistor and LED and confirm your UNO is neither sinking nor sourcing a current… specially confirm your uno is not sinking current… most of my classmates forget 0V is still an output!![/quote]
I checked, it’s working well.

Which picture?

how can I interface an Arduino board then?

Thanks everybody,

Hi,

I don’t understand your question yet.

How all the parameters are assigned correctly when SPI wire is not connected and not powered???

And did you check SPI data signal with oscilloscope??

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