The Daily Duino

There has been quite a flurry of development revolving around the official ethernet shield recently. Here are what I consider a few of the more important changes.

Ethernet fixes – There are some connection issues with the ethernet library with regard to incomplete disconnects. Since the wiznet chip only supports 4 simultaneous connections, this manifests itself pretty quickly if you are trying to poll a server for changes. Etracer, from the arduino forums, found and fixed this problem and has released a new client.cpp as well as detailed the issues in a post to the arduino developers mailing list.

Another recent addition is Ben Combee’s Webduino library, which greatly simplifies processing html forms when using the arduino and ethernet shield as a web server. The library and basic examples are available at: http://code.google.com/p/webduino/

Bjoern Hartmann’s UDP library has also been used for a couple of recent projects including work on DNS/DHCP and fellow Infonomicon member Cynshard’s work on a NTP library. The NTP library is particularly useful since it can be combined with the software Date/Time library to have fairly accurate time without adding a hardware realtime clock to your project.

As you can see, there seems to be a lot of development activity ongoing for the official ethernet shield and since the addition of networking to the arduino greatly expands its possible uses, I think we’ll see even more. Please remember to thank these folks for their code and bugfix contributions…

The Arduino team has recently released an Official Ethernet Shield.  I was having trouble with my Adafruit XPort shield as you have to configure the XPort and it takes a lot of code to get it going.  This Arduino stuff is supposed to be easy and fun, and the XPort is not.  The official ethernet shield though is wonderful.  You have to upgrade the ide to version 12 to get the ethernet library.  The shield uses SPI to communicate (the library takes care of this) so you only loose digital pins 11, 12 and 13.  It also brings all of your pins up in the same location, so that you can mount another shield on top.

The official Ethernet Shield is also ~$40 so its not a bad price.  NKC has them in the states.

I plugged in a board with 3 linear pot’s and edited the basic web server sketch to be a little more to my liking.

When I browsed to the Arduino on port 80, this was displayed

My code is here: http://dailyduino.com/code/ethernetshield/webserver.pde

Writing a sketch for the Ethernet Shield is very easy, change the ip address, maybe the subnet mask, and its pretty easy.