---
title: "Need Help Interfacing W5500 with STM32 via SPI (Data Not Transmitting)"
url: "https://maker.wiznet.io/forum/15761"
markdown_url: "https://maker.wiznet.io/forum/15761/md"
type: "Forum topic"
category: "Serial-to-Ethernet & ConfigTool"
author: "salaasmarcelo"
created: "2025-06-13T14:36:35+09:00"
last_activity: "2025-06-16T09:24:53+09:00"
language: "en"
tags: ["STM32"]
views: 7
replies: 1
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# Need Help Interfacing W5500 with STM32 via SPI (Data Not Transmitting)

## Question

Asked by salaasmarcelo on 2025-06-13 in Serial-to-Ethernet & ConfigTool.

Hi everyone,

I am currently working on a project using the W5500 Ethernet module with an STM32F103 microcontroller, communicating via SPI. I have followed the WIZnet datasheet and reference guides closely.., but I am still facing a problem: I can initialize the W5500 (I get a correct response on reading common registers).., but I am not able to send any data over the network.

I am using the ioLibrary provided by WIZnet, configured in static IP mode. The physical connection seems fine, and the LEDs on the RJ45 port indicate activity. However, packets are not being transmitted, and the TX buffer doesn’t seem to flush. [machine learning course in mumbai](https://www.igmguru.com/machine-learning-ai/machine-learning-training-course-in-mumbai)

Has anyone faced similar issues or have suggestions on debugging this: ?? Could it be timing-related or a socket configuration problem: ??

Would appreciate any insight or working examples using STM32 + W5500 !!

Thanks in advance !!

With Regards,

Marcelo

## Replies

### Reply 1 by Grace_Koo, 2025-06-16

Hello,

For testing with STM32F103, please refer to the following examples which may help you get started:

This example demonstrates a Coremark performance test using the STM32F103RB and W5500 Ethernet chip.
[GitHub Link (wiznetmaker)](https://github.com/wiznetmaker/STM32F103RB_W5500_Coremark_Test)

This is a Gitee repository maintained by our Hong Kong branch. It contains multiple examples combining STM32F10x MCUs with the W5500 chip.
[Gitee Link (WIZnet-HK)](https://gitee.com/wiznet-hk/STM32F10x_W5500_Examples)

We hope these resources are helpful for your testing.

Thank you.

---

Source: https://maker.wiznet.io/forum/15761