---
title: "How to send data by muticast?"
url: "https://maker.wiznet.io/forum/10359"
markdown_url: "https://maker.wiznet.io/forum/10359/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "imeumimeum"
created: "2014-07-08T06:54:44+09:00"
last_activity: "2017-05-04T08:34:27+09:00"
language: "en"
views: 481
replies: 3
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# How to send data by muticast?

## Question

Asked by imeumimeum on 2014-07-08 in Ethernet Chips.

It is W5500,it can’t send data by muticast.

for example :the muticast ip is 224.0.0.1; port is 18688;

u8 MutiCastIp={224,0,0,1};
u16 MutiCastPort=18688;
u8 MutiCastStr=“some data”;

I first creat socket as follow:
socket(6, Sn_MR_UDP, MutiCastPort, Sn_MR_MULTI);
and then send the data:
sendto(6, (uint8_t *)MutiCastStr, sizeof(MutiCastStr), MutiCastIp, MutiCastPort);

I use a software tool to lisen the port,but it can’t receive any data.

Thanks!

## Replies

### Reply 1 by imeumimeum, 2014-07-08

I solved the problem,thanks.

### Reply 2 by smashing, 2014-11-25

how you solved the problem.
I use this code:
u8 MutiCastIp={234,6,6,7};
u16 MutiCastPort=3000;
u8 MutiCastStr[1024];

I first creat socket as follow:
socket(3, Sn_MR_UDP, MutiCastPort, Sn_MR_MULTI);
and then send the data:
len =sendto(3, (uint8_t *)MutiCastStr, 536, MutiCastIp, MutiCastPort);

there is no error of sending len = 536,
but I can not receive any data on PC
Regards,
Smashing

### Reply 3 by hjjeon0608, 2014-12-01

Hi, smashing

I think you should check PC side.
Or router could block broad cast packet.

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Source: https://maker.wiznet.io/forum/10359