W7100A Design

Dear Sir/Madam,
I’m planning to integrate W7100A chip for TCP/IP to RS232 conversion and right now I’m using WIZ107RS module and it works absolutely fine. I will follow the schematic diagram Rev1.4 in the design and will buy the chip from RS UK (758-1036)
For my new design, Could you please advise me on the following:

Can I use alternative components instead of the once on the schematic?

According to your forums the chip comes with boot loader pre-installed, is that means it’s ready to run i.e. Also have 4.03 firmware installed?? I’m a bit confused here!

If NOT could you please advise on how to program it? Programmer needed? Link to where to buy it from in UK? And most importantly how to connect it to the chip (electronic schematic if possible)? Can I use PICKIT3 or JTAG Programmer? Etc.?
I’d like it running 4.03 firmware the same as the module!

Is there anything else that I need to pay attention to in my design?

I already know about W7100-S2E chip which it comes ready to use, but it’s not widely available and prefer to use W7100A.

Thanks a lot for your help and I look forward to hearing from you in the near future.

Kind regards,


Feel free to ask any question to this forum.
this forum is always opened to everybody.

Is your question “How to program(download your image) to W7100A?” Am I right?

If yes, Don’t worry about it.

W7100A can support ISP(In-System-Program) without extra-adapter like as JTAG.
It is possible with the built-in W7100A-BOOT.
W7100A can be just programmed with RS232 cable & ISP tools freely provided by WIZnet.
For more detail, refer to

Thank you.

Thanks a lot for your help, could you (or anybody) please confirm my understanding by answering the following questions:

1- Do I need a special programmer?
2- If not, how to connect to the chip to program it first time? which pins I need? do you have connection diagram?
3- could you please explain the RS232 part you mentioned?
4- if I had the setup all set correctly, can I load 4.03 firmware directly or I need to load special .hex/.bin file first?

Thanks a lot for your help and look forward for your replies.

kind regards

Hello Haider,

We have two kinds of products regarding to W7100A.
One is just W7100A and the other is W7100A-S2E.
When you use W7100A, you have to develop your own code and program it on your MCU by yourself.
Meanwhile, if you use W7100A-S2E then you don’t need to develop your own code and program it onto your MCU because WIZnet provide you with preprogrammed chip.
All what you have to do is to design your own hardware with W7100A-S2E.

But if you use W7100A instead of W7100A-S2E, you can’t get its boot loader of W7100A-S2E anywhere because WIZnet doesn’t open it in public.

I recommend you order W7100A-S2E to WIZnet’s distributors near to you.
Otherwise, you can face to some difficulty after HW design finished.

Thank you.


Hi there,

I have asked a similar question elsewhere but no luck yet and not really any information given to go by.

Is the code for the W7100A-S2E-64 chip the same code as the code for the W7100A-S2E-100 chip and is that the code “WIZ107SRv4_03” which we can download, or is there two versions of the code, one for each package of the W7100 and we need to get hold of different code somehow?

It’s a little confusing to be totally honest as the data sheet for the W7100 makes reference to there needed to be different code associated with PHYCONF SFR for the two differnet chips yet only one download for the code is given?

The W7100 chips are easy to get but to get the W7100A-S2E-64 is a long lead time and much higher MOQ.