---
title: "Multiple clients with WIZ750SR"
url: "https://maker.wiznet.io/forum/14820"
markdown_url: "https://maker.wiznet.io/forum/14820/md"
type: "Forum topic"
category: "Serial-to-Ethernet & ConfigTool"
author: "bigboy061293"
created: "2023-03-03T15:46:23+09:00"
last_activity: "2023-05-30T07:59:13+09:00"
language: "en"
views: 310
replies: 4
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# Multiple clients with WIZ750SR

## Question

Asked by bigboy061293 on 2023-03-03 in Serial-to-Ethernet & ConfigTool.

Hello,

I have 10 modules WIZ750SR.
During the testing, I realize that this module just supports 1 client when it is in the TCP Server mode.
What I want it to increase the maximum clients that it can support upto the maximum numbers within its processing limitation.
Is there any available firmwares that I can use or I have to switch to another chips or modules?

I have used USR-TCP232 for a few months and it allows multiple clients. However, I am looking for the alternatives because of some reasons. I hope you guys can have some time to help on this issue.

Thanks.

## Replies

### Reply 1 by bigboy061293, 2023-05-12

Hi,

It is a big thank if anyone can instruct how to change the socket function in the firmware: reducing the sockets used for UDP and incresing the one used for TCP clients [GitHub - Wiznet/WIZ750SR: WIZnet Serial to Ethernet(S2E) module based on W7500 chip, WIZ107/108SR S2E compatible device](https://github.com/Wiznet/WIZ750SR)

Thanks,
Vu.

### Reply 2 by lawrence, 2023-05-23 (in reply to reply 1)

Hi, @bigboy061293 Currently, WIZ750SR support only 7 sockets and you can use 5,6 as you want. Other socket already defined as config function. (socket 0 is data socket) main socket function is in seg.c you can refer the do_seg() to make your own socket. github.com Wiznet/WIZ750SR/blob/master/Projects/S2E_App/src/Serial_to_Ethernet/seg.c#L114 void add_data_transfer_bytecount(teDATADIR dir, uint16_t len); // Serial debug messages for verifying data transfer uint16_t debugSerial_dataTransfer(uint8_t * buf, uint16_t size, teDEBUGTYPE type); #ifdef _TRIGGER_DEBUG_ uint8_t trigger_error_index = 0; #endif /* Public & Private functions ------------------------------------------------*/ void do_seg(uint8_t sock) { //DevConfig *s2e = get_DevConfig_pointer(); struct __network_info *net = (struct __network_info *)get_DevConfig_pointer()->network_info; struct __serial_info *serial = (struct __serial_info *)get_DevConfig_pointer()->serial_info; struct __firmware_update *fwupdate = (struct __firmware_update *)&(get_DevConfig_pointer()->firmware_update); //#ifdef _SEG_DEBUG_ #if 1 if(tmp_timeflag_for_debug) // every 1 sec { If you want 1 more socket, you can control socket memory size as 2KB for socket 0 in main.c, then you can open socket 5,6,7

### Reply 3 by bigboy061293, 2023-05-30

Hi [@lawrence](https://maker.wiznet.io/u/lawrence)
Thanks for the response, it is good to know that the chip is reserved for this purpose. However, how can I conduct a NRE for my purpose?

Vu.

### Reply 4 by lawrence, 2023-05-30

This is opensource. You can make your own application based on this code.
you can refer the function, *void proc_SEG_tcp_client(uint8_t sock)* in seg.c

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Source: https://maker.wiznet.io/forum/14820