µServer: 8bit webserver
This is a little HTTP Web server and a FTP file server. It is built around an 8bit AVR and a Wiznet LAN module. Once a year I get it out of the box and connect it just for the nostalgia and the delight, that it still works.
The basic idea was to create a simple web server but I wanted to be able to use real .htm and picture files and most important to be able to update the pages through the LAN via FTP. One other issue was the configuration of the IP addresses and ports. This data is stored on the SD card and can also be uploaded via FTP. The system automatically reboots when the config file has been written anew.
The LAN and power connectors.
You can see how small it is compared with an SD card. 
The device is built into a little plastic case. It has several status LEDs for web server, FTP server, SPI and FAT activity. It has the LAN and power connectors on the rear side and the LEDs and inlet for SD card in the front. The parts are mounted on a small etched PCB.
The device is programmed in BASCOM-AVR that already includes the AVR-DOS FAT file system. The routines for interfacing the W5100 are relatively simple.
The complete setup for the W5100 is stored on the SD-card. Changing ports or IP address is just a matter of changing the config file.
The HTTP server (v1.0) currently only supports the GET command. Others will return the 501 "command not implemented". The web pages are stored in the "HTTP" folder on the SD card. Any files can be put in the folder and will dynamically be sent to the client according to the file name given in the GET-request. If the file is not found the famous 404 error is returned. It has a data-throughput of about 26Kb per second. In addition various information can be viewed by opening the "status.htm" file. This file is dynamically created by the system on startup or after a FTP session and gives IP addresses and file system information such as free disk space. The basic server runs nicely but there is still a lot more to be implemented. Future features will be the possibility to update the firmware via FTP. The FTP is still a bit sensitive to wrong parameters. This will eventually be improved.
The Wiznet WIZ810MJ is a module that holds the W5100 IC. The W5100 is a full-featured Ethernet controller designed for embedded applications. It includes a hardwired TCP/IP stack and an Ethernet MAC & PHY. Supported protocols are TCP, UDP, IPv4, even PPPoE and others. It is either interfaced through a parallel bus or an SPI. Its performance is up to 2.6Mb per second and has 4 independent sockets.
The FTP server functions to upload the HTTP files and also works as a file server. It supports guest login and admin login. In guest login only the USER folder can be browsed but not the CONF config folder or the folder that holds the website.
Speed:
25 Kb/s download
2.5 Kb/s upload The server runs a simple HTML-based website stored on the SD-card.
It also has a mobile version. It uses jQuery mobile. With the JQM it is very simple to create a nice mobile web page. There is also a demo interface
of switching ports and receiving live data from the µServer.
