---
title: "Link status polling on W5200"
url: "https://maker.wiznet.io/forum/10211"
markdown_url: "https://maker.wiznet.io/forum/10211/md"
type: "Forum topic"
category: "IO Modules"
author: "nver"
created: "2014-05-08T11:31:17+09:00"
last_activity: "2017-05-04T08:32:45+09:00"
language: "en"
views: 1028
replies: 0
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# Link status polling on W5200

## Question

Asked by nver on 2014-05-08 in IO Modules.

Hi there,

I am using Wiz820io (W5200) for my project and my microcontroller polls the Link status bit (Up/down) to check the ethernet cable connectivity. Generally the system is working Ok but I have noticed one problem. I am seeing is that the link status goes up and down even though the ethernet (good quality new cable) is constantly connected between router and Wiz820io. I have tested it with 3 different rounters and different ethernet cables but results are the same.

I have also noticed that the link goes up and down more often (about 40 times in 8 hours) in when there is a longer the ethernet cable (approx 25meter) is used. For short cables (1meter) it goes down 15 times in 8 hours.

Can you please tell me what could be the reason for it ?

Many thanks

---

Source: https://maker.wiznet.io/forum/10211