---
title: "Communicating with the W5500io"
url: "https://maker.wiznet.io/forum/9863"
markdown_url: "https://maker.wiznet.io/forum/9863/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "jdcowpland"
created: "2014-01-24T09:29:36+09:00"
last_activity: "2017-05-04T08:32:14+09:00"
language: "en"
views: 549
replies: 2
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# Communicating with the W5500io

## Question

Asked by jdcowpland on 2014-01-24 in Ethernet Chips.

I have a W5500io hooked up to a STM device, and I’m sending it messages to ask for the MAC address and gateway address but don’t seem to be getting a valid response. I also can’t find any reference in any documentation to the SPI speed I should be using. I currently have mine set at 42MHz. Is that too fast?

My message looks like this:

[![](https://maker.wiznet.io/forum_uploads/wiznet/original/1X/fb509065e3954374ddf622f107d61dcdfd6e55ff.jpg) 1332×635 151 KB](https://maker.wiznet.io/forum_uploads/wiznet/original/1X/fb509065e3954374ddf622f107d61dcdfd6e55ff.jpg)

## Replies

### Reply 1 by xyj19911129, 2014-03-29

Hello, jdcowpland,

I met the same problem as you did. (using SPI to set gateway, ip, mac. etc)

I checked that the data format is right, (2 bytes offset address, 1 byte control code and then data) but I can not receive the response of W5500, the MISO pin is always 1 (according to the pull-up resisitance).

Have you solved your problem, and would you like to share your experience?

Thanks!

### Reply 2 by jsavage, 2014-03-31

I am intrigued by the diagram. What tool did you use for that?
James

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Source: https://maker.wiznet.io/forum/9863