---
title: "W5500 Modbus TCP/IP client connect issue"
url: "https://maker.wiznet.io/forum/14545"
markdown_url: "https://maker.wiznet.io/forum/14545/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "matz001"
created: "2022-05-10T14:09:53+09:00"
last_activity: "2022-05-10T14:09:53+09:00"
language: "en"
views: 406
replies: 0
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# W5500 Modbus TCP/IP client connect issue

## Question

Asked by matz001 on 2022-05-10 in Ethernet Chips.

Hello,
I’m having some issues trying to use W5500 as modbus TCP client. It seams to be that I can write wiz_NetInfo via SPI to the chip by using wizchip_setnetinfo(&netInfo) because I can read back the written things by using wizchip_getnetinfo(&netInfo).

But I am unable to connect to slave device. Function “connect(s,slave_ip,502)” did not respond with 1 as it should be?!
uint8_t s=0;
uint8_t slave_ip[4]={192,168,1,101};

I also tried to capture the response message, I hope that helps and you can give me a hint to fix this problem
[Untitled.pdf](https://maker.wiznet.io/forum/legacyFile.asp?path=wI8cUlm7j2Uq83LQhlT7uFDMvmc.pdf) (41,8 KB)

---

Source: https://maker.wiznet.io/forum/14545