How you take the button action on the ipod example? i mean, how the arduino know that you click the button?
We'll hopefully have an example sketch to show how to do this by the end of the weekend. But, the 50,000 ft view is this (what we did in the demo videos), and I apologize if my terminology is not precisely correct (but I'm a hardware guy anyway, so I'm forgiven ;D):
1. When the client (ipod) makes a request, you'll get a string of data back (GET / ......). The slash is for the root index.html page. The arduino will return back the response for the webserver (webpage var).
2. We constructed a webpage that had form button inputs sending the data back with the GET HTML mechanism. Basically when a button was hit (say the blue led), we'd send a get response to set the var led to '1', i.e., the ipod would go to the following URL:http://192.168.1.2/?led=1
3. On the arduino side, we'd get this request, but we now would parse the GET / ...... to get the led=1 out of the data. With a switch statement, we could actually check what the led variable was set to (1,2,3) for the red, green, and blue LED on the BlinkM. This would tell the Arduino which button was pressed, and we'd then issues the correct commands in the sketch to control the other pieces of hardware.
For our other demo with the remote control, we parsed the same way, but this time had the Arduino control the PWM signals to the IR LED to send the correct IR codes to the TV and DVD player.a
There are other ways to do this as well. You could POST form data, which doesn't show the variable-value pair in the URL string (it's stored in the header of the incoming packet). You could also do something simpler, which is just have page links that open different pages. You would just have to parse the incoming data for this special page that you are going to do something on based on the link click.
Anyway, I know this is a very high level view, but we'll have a sketch soon that shows this in detail.