---
title: "How does RTR affect page loading time?"
url: "https://maker.wiznet.io/forum/13305"
markdown_url: "https://maker.wiznet.io/forum/13305/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "Maksim"
created: "2019-05-05T03:52:03+09:00"
last_activity: "2019-05-14T06:14:18+09:00"
language: "en"
views: 633
replies: 4
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# How does RTR affect page loading time?

## Question

Asked by Maksim on 2019-05-05 in Ethernet Chips.

I connect w5300 with stm32 on FSMC.

When I set RTR = 1000 the page is loaded 122 mc, but CSS and JS do not have time to boot.

When I set RTR = 100, the page loads in 30 ms and I have time to load the CSS and JS, but after 2-5 update of the page the server crashes. From the register getSn_SR, the wrong values 0x10 or 0x22(udp) are read, although the socket is opened in TCP mode. What could it be?

PS: RCR=2

## Replies

### Reply 1 by becky, 2019-05-10

Your explanation is too short.
Add a description of what target you are communicating with, who the server is and what action you want to perform.

RTR is the Retransmission Time value. If a response is not received after transmitting the packet, retransmission interval is set. I do not know what you mean page loading.

### Reply 2 by Maksim, 2019-05-10 (in reply to reply 1)

Thanks for the reply, I doing the web server on wiznet Http using loopback_tcps from [W5500_EVB/loopback.c at master · Wiznet/W5500_EVB · GitHub](https://github.com/Wiznet/W5500_EVB/blob/master/ioLibrary/Appmod/Loopback/loopback.c)
and my Http parser.
“If the response is not received, the retransmission interval is set.”
Yes, I understand this, but I can not understand how it affects the connection time of the browser with the web server, and, accordingly, the speed of opening the web page.
About the fact that getSn_SR = 0x10, I found it to be related to errartum 1, but why it works is also not clear, although I use the library where it is fixed.

### Reply 3 by becky, 2019-05-10

Hello,

I think it will be faster to see the packet.
Capture the packet with wireshark and attach it here or email becky@wiznet.io

### Reply 4 by becky, 2019-05-14

I checked you mail.

First, I think the HTTP code you wrote is incommon.
Compare the HTTP code we’ve written
If you send me the firmware, I’ll check it out.

![](https://github.githubassets.com/favicons/favicon.svg) [github.com](https://github.com/Wiznet/ioLibrary_Driver/tree/master/Internet/httpServer)

### [ioLibrary_Driver/Internet/httpServer at master · Wiznet/ioLibrary_Driver](https://github.com/Wiznet/ioLibrary_Driver/tree/master/Internet/httpServer)

[master/Internet/httpServer](https://github.com/Wiznet/ioLibrary_Driver/tree/master/Internet/httpServer)

ioLibrary_Driver can be used for the application design of WIZnet TCP/IP chips as W5500, W5300, W5200, W5100 W5100S.

![](https://github.githubassets.com/favicons/favicon.svg) [GitHub](https://github.com/Wiznet/HTTPServer_LPC11E36_LPCXpresso)

![](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/d/dc97428cf8e32014e07e1e22b14ab4811f94f619.png)

### [GitHub - Wiznet/HTTPServer_LPC11E36_LPCXpresso: WIZnet W5500 / NXP LPC11E36...](https://github.com/Wiznet/HTTPServer_LPC11E36_LPCXpresso)

WIZnet W5500 / NXP LPC11E36 based Web server example project - GitHub - Wiznet/HTTPServer_LPC11E36_LPCXpresso: WIZnet W5500 / NXP LPC11E36 based Web server example project

---

Source: https://maker.wiznet.io/forum/13305