---
title: "W5500 + RP2040 custom board"
url: "https://maker.wiznet.io/forum/15260"
markdown_url: "https://maker.wiznet.io/forum/15260/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "Debanshu Bhaumik"
created: "2024-08-09T05:37:02+09:00"
last_activity: "2024-08-13T07:55:16+09:00"
language: "en"
views: 27
replies: 4
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# W5500 + RP2040 custom board

## Question

Asked by Debanshu Bhaumik on 2024-08-09 in Ethernet Chips.

Hello everyone,

First of all I am fairly new to this community and thankyou for having such a great community.

I have tried to create a custom W5500 + RP2040 custom board. While designing the board I have referenced the schematic available on

![](https://github.githubassets.com/favicons/favicon.svg) [github.com](https://github.com/Wiznet/Hardware-Files-of-WIZnet/tree/master/02_iEthernet/W5500)

### [Hardware-Files-of-WIZnet/02_iEthernet/W5500 at master ·...](https://github.com/Wiznet/Hardware-Files-of-WIZnet/tree/master/02_iEthernet/W5500)

This repository is a place to manage hardware-related data created by WIZnet. - Wiznet/Hardware-Files-of-WIZnet

I got the boards fabricated and when they came in, there wasn’t any Link Led light when I plugged the RJ45 connector into the board. It was strange as there should be Link Led light.

I am using Arduino IDE to program and started to debug. I could see that the w5500 `Ethernet.hardwareStatus() ` was detected but there was no link `Ethernet.linkStatus()`. I am using Ethernet Library in arduino. I am also using UDP to send / receive data.

After going through a few articles, I followed instructions mentioned in this article

![](https://avatars.discourse-cdn.com/v4/letter/m/d26b3c/48.png) [W5500 No PHY Link](https://forum.wiznet.io/t/topic/2614/3) [W5500](https://maker.wiznet.io/c/tcp-ip-chip/w5500/18)

> Hi, Same issue here. PCB designed according to ref. schematics, produced in factory Plug in w5500 to Cisco switch, link does not come up But when I disable Auto-negotiation on Cisco switch, port is UP. This is on 100Mbit port, and on 1Gbit port, I need to disable Auto-negotiation and manually set port speed to 100Mbit. This is happening on different Cisco switches, 2960 series and SF-300 series Thing is that I cannot un-solder resistor to disable auto-negotiation on pcb since it is resisto…

I set the PHYCFGR register.

1. Half Duplex 10 - Link LED constantly ON

2. Full Duplex 10 - Link LED constantly ON

3. Half Duplex 100 - Link LED off | non responsive state

4. Full Duplex 100 - Link LED off | non responsive state

5. Full Duplex 100 with Auto Neg - Link LED off | non responsive state

6. Auto Neg - Link LED off | non responsive state

Observations :

1. In the Half/full duplex 10 mode, I can see that the link is up but I am not able to send or receive data through UDP.

2. If I configure w5500 in Half/full duplex 10 mode, then I am able to configure them in Full Duplex 100 mode as well, but as soon as power down the board and then power it up again, the Link Led is off and the link is down. Then I have to configure w5500 in Half/full duplex 10 mode again for the link LED to be ON.

I am using a very dumb router DLink 1005c

![](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/4/4cab26a33b154ec58b80c0e1f39890bc31c5dadd.png) [D-Link](https://www.dlink.com/in/en/products/des-1005c-5-port-10-100-mbps-unmanaged-desktop-switch)

![](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/5/5feeeaf82a9af552b1406549585c8f8922b258f8.png)

### [DES‑1005C - 5-Port 10/100 Mbps Unmanaged Desktop Switch](https://www.dlink.com/in/en/products/des-1005c-5-port-10-100-mbps-unmanaged-desktop-switch)

5 high-speed Fast Ethernet ports Innovative D-Link Green energy saving features Compact design for convenient placement Fanless design for silent operation

Any help or directions on this will be very helpful.

Many Thanks,

[Schematic_PICO+5500_2024-07-18.pdf](https://maker.wiznet.io/forum/legacyFile.asp?path=z0WLXX74ms1UQvgSq6OxasDmuTP.pdf) (210.1 KB)
[Gerber_PICO+5500_PCB_PICO+5500_2_2024-08-09.zip](https://maker.wiznet.io/forum/legacyFile.asp?path=mppRvMnsjoUSuKZvahpZNeKbj48.zip) (152.5 KB)

## Replies

### Reply 1 by Eugeny, 2024-08-09

Debanshu_Bhaumik:

> It was strange as there should be Link Led light.

Correct, it should if PHY is not configured down and powered up and not in reset state.

I did not look into the circuit closely, brief look did not show any fatal problems (unless some pins are confused).

First thing to check is power. Second thing to check is clock. But thing number 0 to check is what is on the board in reality vs circuit diagram. For example, do you have 49.9k resistors instead of 49.9 Ohms soldered.

### Reply 2 by Debanshu Bhaumik, 2024-08-09 (in reply to reply 1)

Thankyou for your response.

Eugeny:

> Debanshu_Bhaumik:
>
> > It was strange as there should be Link Led light.
>
> Correct, it should if PHY is not configured down and powered up and not in reset state.
>
> I did not look into the circuit closely, brief look did not show any fatal problems (unless some pins are confused).
>
> First thing to check is power. Second thing to check is clock. But thing number 0 to check is what is on the board in reality vs circuit diagram. For example, do you have 49.9k resistors instead of 49.9 Ohms soldered.

Eugeny:

> Debanshu_Bhaumik:
>
> > It was strange as there should be Link Led light.
>
> Correct, it should if PHY is not configured down and powered up and not in reset state.
>
> I did not look into the circuit closely, brief look did not show any fatal problems (unless some pins are confused).
>
> First thing to check is power. Second thing to check is clock. But thing number 0 to check is what is on the board in reality vs circuit diagram. For example, do you have 49.9k resistors instead of 49.9 Ohms soldered.

I have checked and powered the chip through an external power supply but the same results as stated above.

I will double check the values on board and update here.

Thanks.

### Reply 3 by Debanshu Bhaumik, 2024-08-13 (in reply to reply 1)

[@Eugeny](https://maker.wiznet.io/u/eugeny) - I tried out a few more things.

Check 0 : All the values of the resistances used are fine and within the 1% limit.
Check 1 : Powered through external power supply directly to the w5500, still the same behviour.
Check 2 : The crystal seems fine delivering 25MHz.

I was going through the hardware design parameters

[docs.wiznet.io](https://docs.wiznet.io/img/design_guide/Wiznet%20Ethernet%20Design%20Guide_ENG.pdf)

<https://docs.wiznet.io/img/design_guide/Wiznet%20Ethernet%20Design%20Guide_ENG.pdf>

### [Wiznet%20Ethernet%20Design%20Guide_ENG.pdf](https://docs.wiznet.io/img/design_guide/Wiznet%20Ethernet%20Design%20Guide_ENG.pdf)

2.19 MB

Do you think that the problem lies in the artwork?

### Reply 4 by Eugeny, 2024-08-13

Debanshu_Bhaumik:

> Do you think that the problem lies in the artwork?

Not sure I understand what you mean.

As far as we are sure hardware must be ok (hopefully chip was not overheated during manufacturing), you seem to have SPI access functioning. Please prove it by reading VERSIONR register.

Next test is you remove ALL the driving code, and leave only the following:

- hardware reset using RST pin

- software reset using MR register

- reading VERSIONR to ensure you read 0x04

- stop (infinite loop).

With this set up chip is in default state, PHY is enabled. Now when you plug cable in - try both direct and crossover, with one of these cables you must have link LED on, *but only* in case another end of cable is connected to the port which is up.

---

Source: https://maker.wiznet.io/forum/15260
