---
title: "W5200 Polarity Reversal Detection"
url: "https://maker.wiznet.io/forum/12351"
markdown_url: "https://maker.wiznet.io/forum/12351/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "Dan"
created: "2017-06-30T01:33:02+09:00"
last_activity: "2017-07-01T16:44:53+09:00"
language: "en"
views: 848
replies: 1
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# W5200 Polarity Reversal Detection

## Question

Asked by Dan on 2017-06-30 in Ethernet Chips.

Hello,

We are running a loopback test on our device which has the W5200.
Our device will send data to a script running on a PC, which then sends the data back to the device.
But we have found that the test still passes when we swap the TX+ and TX- lines on our cable.
We also swapped the RX+ and RX- lines and the test still passes.

I know some Ethernet transceivers have polarity detection and correction built in.
Does the W5200 have that feature? There’s nothing listed in the datasheet.

## Replies

### Reply 1 by Eugeny, 2017-07-01

I think you have answered your question yourself.
Thank you for sharing your test results!

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Source: https://maker.wiznet.io/forum/12351