---
title: "[Multicast] Unable to receive"
url: "https://maker.wiznet.io/forum/14068"
markdown_url: "https://maker.wiznet.io/forum/14068/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "Roger S Sacchelli"
created: "2020-11-14T17:35:26+09:00"
last_activity: "2020-11-14T17:46:40+09:00"
language: "en"
views: 470
replies: 1
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# [Multicast] Unable to receive

## Question

Asked by Roger S Sacchelli on 2020-11-14 in Ethernet Chips.

Hi,

I’m having some issues to receive multicast frames with W5500.

Initialization seems to be normal but receive buffer never changes from zero.

![image](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/b/b29244616c66d10215f41a766783d723e4756784.png)

> [INFO]SPI Initialized
> [INFO]Global Interruptions Enabled
> ---------- DHCP INIT ---------
> [INFO]HW ADDR: 0:8:dc:22:1:88
> SOCK STATUS 0: SOCK_UDP
> SOCK STATUS 1: SOCK_UDP

Socket 0 is set for UDP, port 4000 which I can receive data normally.
Socket 1 is set for UDP+MCAST, port 49707 which I cannot receive anything.

First question would be if something is being set for the intended group, and the question is yes, I sniffed w/ wireshark and the router is forwarding to the group every second:

`1 0.000000 192.168.0.1 239.255.1.1 UDP 81 49707 → 49707 Len=39`

Appreciate any help!

## Replies

### Reply 1 by Roger S Sacchelli, 2020-11-14

Fortunatelly I was able to fix the issue.

I had forgotten to add the DPORT instruction. ![:face_with_raised_eyebrow:](https://emoji.discourse-cdn.com/twitter/face_with_raised_eyebrow.png?v=12)

![image](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/f/f3c2bc55d3a58266e735193857da7560d84eba8f.png)

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Source: https://maker.wiznet.io/forum/14068