---
title: "W5500 Ethernet module"
url: "https://maker.wiznet.io/forum/14537"
markdown_url: "https://maker.wiznet.io/forum/14537/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "yash vadict"
created: "2022-04-27T06:02:52+09:00"
last_activity: "2023-12-12T09:19:38+09:00"
language: "en"
views: 600
replies: 1
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# W5500 Ethernet module

## Question

Asked by yash vadict on 2022-04-27 in Ethernet Chips.

Hello,

I’m using a W5500 module with 27Mhz of STM32 SPI clock and I’m sending 1800 bytes every 8ms for 20 seconds. I have created a private network, the module is connected to the laptop and in the module’s physical configuration I have set 100Mbps speed. After 20 seconds, should have received 2500 packets but some packets are missing and I have checked the speed with Wireshark which is around 200KBPS to 230KBPS. And when I checked with 1460 bytes, the speed comes down to 30KBPS.
So why I’m not getting actual speed?

Thanks.

## Replies

### Reply 1 by teddy, 2023-11-23

![](https://avatars.discourse-cdn.com/v4/letter/y/bcef8e/48.png) yash_vadict:

> STM32 SPI 클록을 갖춘 W5500 모듈을 사용하고 있으며 20초 동안 8ms마다 1800바이트를 전송하고 있습니다. 개인 네트워크를 만들었고 모듈이 노트북에 연결되었으며 모듈의 물리적 구성에서 100Mbps 속도를 설정했습니다. 20초 후에 2500개의 패킷을 받았어야 했는데 일부 패킷이 누락되어 Wireshark로 속도를 확인했는데 약 200KBPS~230KBPS입니다. 그리고 1460바이트로 확인해 보니 속도가 30KBPS까지 떨어지더군요.

Hello, is the communication protocol TCP or UDP? Given that there’s talk about 1460 bytes in Wireshark, it seems like it might be TCP. Did you use the IoLibrary? Did you register and use functions like spi read and write burst?
How did you configure the SPI settings in the STM? Did you use DMA?
When you checked the Wireshark packets, were 1800 bytes transmitted every 8ms, excluding any missing ones?
Was the 8ms timing checked and transmitted using a timer counter?
There is not enough information provided. There are many variables in the program, so please confirm.

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Source: https://maker.wiznet.io/forum/14537