---
title: "schematic for WIZ107SR-TTL"
url: "https://maker.wiznet.io/forum/12684"
markdown_url: "https://maker.wiznet.io/forum/12684/md"
type: "Forum topic"
category: "Serial-to-Ethernet & ConfigTool"
author: "kslam1980"
created: "2018-01-28T04:08:16+09:00"
last_activity: "2018-06-14T02:26:16+09:00"
language: "en"
views: 2800
replies: 35
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# schematic for WIZ107SR-TTL

## Question

Asked by kslam1980 on 2018-01-28 in Serial-to-Ethernet & ConfigTool.

I’m having the WIZ107SR-RS232 here, but I would like to use it as TTL instead of the RS-232.
Referring to the schematic wiz107sr_rev1_4.pdf for WIZ107SR, is the following step correct to make it as TTL version:

- ```
     remove the R21, R22, R23, R24
```

- ```
     remove the U2
```

- ```
     add the R38, R39, R40, R41
```

## Replies

### Reply 1 by Edward, 2018-01-29

Hi. kslam1980

Yes exactly.

Thank you.

### Reply 2 by kslam1980, 2018-01-30 (in reply to reply 1)

Hi Edward,

In theWIZ107SR User Manual, 2.1.1 Network Configuration, it mentions that the configuration can be saved in the EEPROM. However, seem like the EEPROM is not been populated on the module itself, so does it means this function won’t work?

1. Setting
   This function is to complete the configuration change.
   If you select the MAC Address from the “Serial to Ethernet” tree, the default
   configuration value of the module will be displayed. Change the configuration and click
   “Setting” button to complete the configuration. The module will re-initialize with the
   changed configuration. Changed value is saved in the EEPROM of the module. Thus, the
   value is not removed even though power is disconnected.

Thanks & Regards,
KS Lam

### Reply 3 by Edward, 2018-02-01

Hi KS Lam

WIZ107SR is not mounted EEPROM.
And WIZ107SR has two memories that code flash and data flash.

code flash has the application operation and data flash has configuration tool (network and serial setting value).

I recommend you that not mount EEPROM.

Thank you

### Reply 4 by kslam1980, 2018-02-05

Hi Edward,

Currently, we are thinking to integrate the W7100A into our custom board.

- ```
     Is the W7100A chip pre-programmed with the correct firmware?
```

- ```
     How can we upload the new firmware into the W7100A? Is it we need to tie the BOOTEN pin to VDD to upload new firmware?
```

- ```
     Can you provide me the BOM list of the WIZ107SR for reference purpose?
```

Thanks & Regards,
KS Lam

![](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/f/f464dd1c7c382c015b3fc53eebe1cd1aadffee61.jpg)

### Reply 5 by Edward, 2018-02-09

Hi. KS Lam

![](https://avatars.discourse-cdn.com/v4/letter/k/90db22/48.png) kslam1980:

> Is the W7100A chip pre-programmed with the correct firmware?

The firmware file of the W7100A chip pre-programmed same as WIZ107SR firmware.
So I refer to WIZ107SR firmware file.[WIZ107SRv4_06p.zip](https://maker.wiznet.io/forum/legacyFile.asp?path=nYRYgtemcAVjqaJtFkuk5ger7UW.zip) (22.6 KB)

![](https://avatars.discourse-cdn.com/v4/letter/k/90db22/48.png) kslam1980:

> How can we upload the new firmware into the W7100A? Is it we need to tie the BOOTEN pin to VDD to upload new firmware?

W7100A firmware upload uses WizISP tool.
First, it set to high with BOOTEN pin(VCC). And active reset (low) and then access WizISP tool.
WizISP tool user’s guide is inside zip files. refer to inside guide.

refer to below link.
<http://old.wiznet.co.kr/sub_modules/kr/resources/Download_View.asp?PK_Num=458&page=11&SF_Part=&SF_KeyWord=>

And refer to BOM pdf file. [WIZ107SR Rev1.4 Partlist_TTL.pdf](https://maker.wiznet.io/forum/legacyFile.asp?path=9o7LCK8R2D4TxpPePpB4EM1JqIJ.pdf) (72.0 KB)

Thank you.
Best regards,
Edward

### Reply 6 by kslam1980, 2018-05-19

Do you have the source code for the WIZ107SRv4_06p.zip?
What is the default configuration (baudrate, parity, stop bit etc) of UART for the pre-programmed W7100A chip?

### Reply 7 by Edward, 2018-05-21

Hi.

If you want WIZ107SR source code, and you must contact to us to NON-DISCLOSURE AGREEMENT.
So, Please contact to our US office.

And, W7100A default serial setting is refer to below list.

1. baudrate: 57600 bps

2. Data bit: 8 bit

3. Parity: none

4. Stop bit: 1
   5.Flow Control: none

Thank you.

### Reply 8 by Edward, 2018-05-21

US office contact point is refer to below link.
<http://www.wiznet.io/about/contact-us/>

Thank you.

### Reply 9 by kslam1980, 2018-05-22 (in reply to reply 8)

Hi Edward,

How to update the MAC address of the W7100A chip? Is it using the WizMAC tool? Where am I able to download that tool?

Thanks & Regards,

KS Lam

### Reply 10 by Edward, 2018-05-23

Hi.

It can update MAC address to using terminal tool.
You just send this serial message “MC00:08:DC:xx:xx:xx$0d$0a”.

xx blank is insert your mac address.

Thank you

### Reply 11 by kslam1980, 2018-05-28

In my design, i’m using two sets of W7100A to work as the serial to ethernet converter, base on the WIZ107SR reference design. I’m able to establish the connection to each of this individual sets of W7100A to PC through the RJ-45 port. However, when i perform a back-to-back connection from one RJ-45 port on my design to the other RJ-45 port on my design, the Green LED light on the RJ-45 doesn’t light up. It seems the back-to-back connection is not linked. What could be the possible problem in this case?

### Reply 12 by Edward, 2018-05-30 (in reply to reply 11)

Hi.

please tell me connection diagram.
each W7100A can search on configuration tool?
If you possible search on configuration tool, I think it has connected problem.
So tell me connection diagram.

Thank you

### Reply 13 by kslam1980, 2018-05-30

Hi Edward,

Yes, each W7100A can be searched through the configuration tool.
What kind of connection diagram you are referring here?

Thanks & Regards,
KS Lam

### Reply 14 by Edward, 2018-05-30

Hi KS Lam

How connected to each W7100A board?
I think, if you can be searched on configuration tool, your connection is wrong.
So, how connect to each w7100A?

Thank you

### Reply 15 by kslam1980, 2018-05-30

Hi Edward,

Here is the connection diagram on how i connect both W7100A together.

Thanks & Regards,
KS Lam

[![IMG_20180530_154926](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/6/6d3201f38dd7aea48e58b5cbe4238242db3b54e6.jpg) IMG_20180530_1549261180×592 144 KB](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/6/6d3201f38dd7aea48e58b5cbe4238242db3b54e6.jpg)

### Reply 16 by Edward, 2018-05-31 (in reply to reply 15)

Hi. KS Lam

You have to different set each W7100A.
For example, left W7100A set TCP server and right W7100A set TCP client.
You don’t directly connection. You must connect with HUB.
(W7100A) — (LAN cable) — (HUB) — (LANCable) — (W7100A)

However If it doesn’t working, you should test each W7100A. such as loopback test.
If each W7100A loopback test is work well, I think it is wrong hub or not good connection.

Thank you

### Reply 17 by kslam1980, 2018-05-31

Hi Edward,

Actually i did a similar setup using the WIZ107SR module, and i was able to establish the link without going through the hub as following.

(WIZ107SR) – (LAN cable) – (WIZ107SR)

So, i wonder why it doesn’t work in this case with our custom board setup.

I did the loop back test for each individual W7100A, and it is working.

Thanks & Regards,
KS Lam

### Reply 18 by Edward, 2018-05-31

I will update u once thHi KS Lam.

When you connect to each w7100A directly, ACT/LINK LED is blink?

I don’t know why it doesn’t working…
So, We need to many the other ways…
If you fine, connect with HUB.

And Can you confirmed circuit from us?

Thank you

p.s I recommaend that use direct lan cable.

### Reply 19 by kslam1980, 2018-05-31

Hi Edward,

When i connect the (W7100A) - (LAN cable) - (W7100A) directly, the LINK LED doesn’t light-up/blink.
I have tried with both the direct and cross LAN cable, and it doesn’t work for both cases.
In our application, we will need it to be able to connect directly without going through the hub.
Yes, the circuit is based on the reference circuit of WIZ107SR (rev1.4).

Thanks & Regards,
KS Lam

### Reply 20 by Edward, 2018-05-31

Hi KS Lam.

I think, It doesn’t light-up/blink to ACT or LINK LED, You must use hub…
So, please consider to use hub. and please test with HUB.

Thank you

### Reply 21 by kslam1980, 2018-05-31

Hi Edward,

If it is the limitation of the chip that need to go through a hub, but how can we explain that we can actually setup the link with (WIZ107SR) - (LAN cable) - (WIZ107SR) setup?

Thanks & Regards,
KS Lam

### Reply 22 by Edward, 2018-06-01

Hi KS Lam.

The fact is your board didn’t link up.
So I gave to the other solution.

I don’t know what is problem, Again send to me your schematic files?

Thanks.

### Reply 23 by kslam1980, 2018-06-01

Hi Edward,

Please refer to the following for the schematic…

[![page1](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/c/c68252c2e0cfe6473a8fd5b3a2468bb273e35ca0.png) page11196×807 79.2 KB](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/c/c68252c2e0cfe6473a8fd5b3a2468bb273e35ca0.png)

[![page2](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/d/de7171e51a4f96b52d14b0a7a27c9cd08a2df5d2.png) page21175×801 77.8 KB](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/d/de7171e51a4f96b52d14b0a7a27c9cd08a2df5d2.png)

Thanks & Regards,
KS Lam

### Reply 24 by Edward, 2018-06-01

Hi.

Please give me schematic PDF file.
And give me gerber files each W7100A board.

Thanks

### Reply 25 by kslam1980, 2018-06-01

Hi Edward,

Can you provide me your email address which i can send the file to you directly? As our company policy not allow us to reveal the schematic & gerber in open forum.

Thanks & Regards,
KS Lam

### Reply 26 by Edward, 2018-06-04 (in reply to reply 25)

Hi KS Lam.

My email is edward@wiznet.io.

Thanks

### Reply 27 by kslam1980, 2018-06-04

Hi Edward,

Have emailed you the schematic & gerber.
Besides, do you have the IBIS model for W7100A chip and RB1-125BAG1A (RJ-45 connector)?

Thanks & Regards,
KS Lam

### Reply 28 by Edward, 2018-06-04

Hi. KS Lam.

We only have datasheet and WIZ107/108SR Circuit.
Did you already have WIZ107SR schematic?

Thanks

### Reply 29 by kslam1980, 2018-06-04

Hi Edward,

Yes, I already have the schematic for WIZ107SR module.
Any finding on the schematic and Gerber that I have sent to you earlier?

Thanks & Regards,
KS Lam

### Reply 30 by Edward, 2018-06-04

Hi. KS Lam.

I looked at your schematic.
And your circuit has wrong termination resistor.
It is 49.9R ohm, not 49.9K.

This part modify and test again.

![image](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/f/fd57ba9221407c9e782b5819c5ab8a9c08c3f632.png)

Thanks

### Reply 31 by Edward, 2018-06-04

Hi KS Lam

And refer to below link. (Design Guide)
please refer to Parts Placement section in design guide
<https://wizwiki.net/wiki/doku.php?id=design_guide:hardware:start>

You didn’t erase inner 1, 2 layer Copper GND.
You must erase Copper GND to below RJ45 area.
And Do not place parts to below RJ45.

Thanks

### Reply 32 by kslam1980, 2018-06-04 (in reply to reply 31)

Hi Edward,

Can you send me the gerber for the WIZ107SR module, so that we can refer to it.

Thanks & Regards,

KS Lam

![](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/f/f464dd1c7c382c015b3fc53eebe1cd1aadffee61.jpg)

### Reply 33 by Edward, 2018-06-05

I sent your e-mail.

please check your e-mail.

Thanks

### Reply 34 by kslam1980, 2018-06-05

Hi Edward,

Thanks for the gerber…

Thanks & Regards,
KS Lam

### Reply 35 by Edward, 2018-06-14 (in reply to reply 34)

Your welcome~

---

Source: https://maker.wiznet.io/forum/12684