---
title: "W5500 Link Led will work sometime"
url: "https://maker.wiznet.io/forum/13192"
markdown_url: "https://maker.wiznet.io/forum/13192/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "Century"
created: "2019-02-01T13:33:34+09:00"
last_activity: "2024-06-21T00:01:53+09:00"
language: "en"
views: 657
replies: 7
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# W5500 Link Led will work sometime

## Question

Asked by Century on 2019-02-01 in Ethernet Chips.

Hi,

we have made W5500 custom board and SPI works fine. But when I kept chip in listen mode and Ethernet cable is connected but Link LED not establishing. I even checked the Sn_SR Register and the response I got as chip is in Listen Mode.

Only two times I saw the Link LED was glowing and after that never glowed Link LED.

Is there any time delay required to establish Link LED?

Please help me!

## Replies

### Reply 1 by Eugeny, 2019-02-01

Post circuit diagram please. |Most probably you are having the issues with PHY circuitry, or with clock circuitry.

### Reply 2 by Century, 2019-02-02 (in reply to reply 1)

[ETHERNET PDF.pdf](https://maker.wiznet.io/forum/legacyFile.asp?path=tEJT9Ci5scDPvcBhQpSR59u0Uca.pdf) (22.8 KB)

### Reply 3 by Eugeny, 2019-02-02

Seems to be exact copy of reference schematic, except R2 which must not make a difference. Don’t you accidentally have PHY disabled through PHYCFGR? Try playing with its contents to see if there’s any change.

### Reply 4 by Century, 2019-02-02

I am always getting 10111010 response for PHYCFGR. That means it is configured correctly.

In circuit TX/RX resistor values are correct? I kept 33R instead of 0R.

### Reply 5 by Eugeny, 2019-02-02

LSB of 0 suggests that there’s really no physical link.

There were people changing 33 to 0, but if I recall properly it was not that bad as you describe. But anyway it is a good idea to change them to 0 (shorts) as a test. Also examine board with magnifier to ensure it has no assembly issues.

### Reply 6 by Century, 2019-02-02

Ok, Thank you will try that.

### Reply 7 by benjonson, 2024-06-13

Why my post is showing this error?
Please guide me and live my post.

[![Screenshot (238)](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/3/3d0d7d9aebcbe41f2c41142c75785a2259300e03.png) Screenshot (238)1920×1080 225 KB](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/3/3d0d7d9aebcbe41f2c41142c75785a2259300e03.png)

---

Source: https://maker.wiznet.io/forum/13192