WIZ550web not reprogramming correctly


I’ve tried reprogramming the WIZ550web according to the datasheet through the use of the STMFlashLoader Demo program and I ensured that I followed the loading of the boot.bin at address 0x8000000 and the app.bin at 0x8006000.

But when the board boots up, it does not initialize the Wiz5500 chip or the demo webpage. On the serial line it writes: “Medium Density Flash memory Input Mac ?” Whenever I try to input any command, it replies back with “Input Mac ?” for every character.

Any ideas if I am doing something wrong/incomplete? Or is there a command I need to follow up with?


Hi, VoltageDivider.
I think this issue caused by the global erase of code flash memory for ‘boot’ part programming.
WIZ550web stored configuration data in the end of the 2-bytes of the code flash memory.
(e.g., MAC address, Netinfos and etc.)


<= Oops! There was a fix. not 2-bytes, ‘2kB’ of the code flash memory.

So, after ‘Boot.bin’ successfully programmed once, we recommend to program the modified ‘App’ part at address 0x80006000 only. (using configtool Tftp or ST flash loader)

Note that, Input method for MAC address is as follows.
Terminal> S0008dcxxxxxx


Hi Eric, Hi Voltage Divider,

I received a couple of WIZ550web modules two weeks ago. I’ve spent a bunch of time figuring out almost everything about these things plus the software. I will say the software is a work of art. The team at Wiznet has created a pretty useful device and open source software to go with it.

My first challenge was to get the software to compile. I discovered that some of the Eclipse makefile “rule” files are flawed in the distribution for the WIZ550web_Boot module. Under the “Debug/src” path, look for all the “subdir.mk” files and modify the build command line from -I"D:\WIZnet__Purple\WIZ550WEB\workspace\WIZ550web_Boot\src\xxxxxx" to “…\src\xxxxx”. This is to include various header files that won’t be found unless the path is modified to something useful. I assume the original developer had a Windows system with a “D:” drive containing these headers or this entire project. It is much easier just to change these statements in each instance of the “subdir.mk” files to be relative locations rather than absolute locations that will probably only work on the original developer’s computer. I’ve also ported the project to my MAC after I discovered the problems.

For everybody unfamiliar with Eclipse, loading the project in Eclipse is pretty easy as long as you keep everything else the same. I have two projects. One for Boot and one for App.

The second topic, and the real reason I responded is that I found it was absolutely impossible to make the example work as shown on the Youtube video. Smoke and Mirrors is all I can say. I am running the latest versions of the ST Flash Loader and it is flawed. It will not relocate a binary file to 0x8006000. No way I could make that work. Best way to fix this problem is to create a HEX file for the “APP” and once you do that, and use that as the input to the ST Flash Loader, the ST Flash Loader and the full set of software works great.

I’ve started working exclusively with the very latest version of the software version 1.1.0 and I’m working to get all the warts out of the various parts of it. I see it always error out when I attempt to FTP into the board and upload the code the first time. The second time it works fine. I spent an hour trying that one and then resetting the board. Forget the reset and just try connecting again and uploading. It works the second time around. Hope to have that fixed soon. I also see random resets. Not sure what is bombing. Another bug-a-boo is that every time an I/O port changes, it appears that the SW writes the status to the internal flash. After 10,000 writes that will be history. Unfortunately ST does not make that easy with their parts. The best answer is to write to RAM and just be done with it. I’m looking into writing the status and the config tables to Dataflash, but I have not figured that out yet. That will give you at least 100,000 changes.

I also noticed a really poor speed when using the Dataflash. I’m trying to figure out how to get that resolved. I love the Dataflash idea, but 10 seconds to load the page is ridiculous.

I’ve built a define statement to cause the “App” version, when compiled to load at 0x8000000 instead of 0x8006000, and I added the MAC configuration command in that module to allow the device to operate with a smaller footprint. I understand the “boot” concept, but that pushes the code to the limit.

Anyway, post a note and I might have an answer for all the stuff I’ve figured out. It is about the simplest three chip web server I’ve encountered. If I can only get more memory for adding FreeRTOS and some other useful stuff to use as a project baseline. Wiznet has created a masterpiece.


Hi, Chuck.
Thank you for your important advices.
You have mentioned are important points. We will try to update the pointed out issues soon.

we expect more improvement points from user’s opinion.
Thanks again.


Hi, VoltageDivider.

I’ve had a similar experience. So I extracted the binary code from mcu by using ST flash loader and compared with original code.

Extracted binary code was different from original binary code. It was APP bin code not BOOT bin code at address 0x08000000.

Conclusion is new version(2.7.0? I don’t remember.) of ST flash loader can’t write start at address 0x08006000. Always start at 0x08000000.

Please try to use previous version.