---
title: "W5100 won't connect when ping times > 200ms"
url: "https://maker.wiznet.io/forum/14314"
markdown_url: "https://maker.wiznet.io/forum/14314/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "JLCJoe"
created: "2021-07-29T19:30:02+09:00"
last_activity: "2021-07-30T00:26:46+09:00"
language: "en"
views: 319
replies: 1
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# W5100 won't connect when ping times > 200ms

## Question

Asked by JLCJoe on 2021-07-29 in Ethernet Chips.

Does anyone know why the W5100 (TCP Server) does not accept connections when the ping times are long (>200ms)? Short ping times (<100ms) are ok.

We tried setting the Retry Time Register to 800ms and the Retry Count Register to 255 and the issue still occurs.

Thanks.

## Replies

### Reply 1 by louis, 2021-07-30

Hello.

RTR sets initial value of Sn_RTR (SOCKET n Retransmission Time Register). The unit is 100us.
RTR and RCR (Retransmission Counter Register) set ARP & TCP Retransmission.

[![image](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/8/8764fb36823e86be196073c1500c8dff9dd44d89.png) image757×608 133 KB](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/8/8764fb36823e86be196073c1500c8dff9dd44d89.png)

Thank you

---

Source: https://maker.wiznet.io/forum/14314