---
title: "W5300 can't change up address"
url: "https://maker.wiznet.io/forum/14344"
markdown_url: "https://maker.wiznet.io/forum/14344/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "Mehrshad Jafarinejad"
created: "2021-09-06T12:48:59+09:00"
last_activity: "2021-09-08T00:03:59+09:00"
language: "en"
views: 394
replies: 1
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# W5300 can't change up address

## Question

Asked by Mehrshad Jafarinejad on 2021-09-06 in Ethernet Chips.

Hello.
I want to make a TCP server using w5300
I first write IP address to SIPR register but when I read it again, It doesn’t change and is constant.
Can you help me?

## Replies

### Reply 1 by louis, 2021-09-08

Hello,

![image](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/9/91751d7f15d2a2a3f029e4281340554f320a51f4.png)

SIPR has two register addresses. You can check the address by writing and reading the register on each of SIPR and SIPR2.

Thank you.

---

Source: https://maker.wiznet.io/forum/14344