I have a sensor that is hooked up to a analog port on my Arduino Uno with official WIFI shield. The sensors output is sent to the local server, that the Arduino is hosting, and displaying it fine. How do i update the number dynamically without refreshing the whole page? I know I can use AJAX but that is too heavy on an Arduino I would think, and where should you connect javascript in the Arduino code if that is the only way out?
Cheers
The sensors output is sent to the local server, that the Arduino is hosting
Rubbish.
without refreshing the whole page?
Use frames.
Using AJAX is convenient and is more to do with the client side, that is, the javascript running on the client.
With AJAX, you can make requests for data, where the Arduino can simply respond with the data, say as json formatted within HTTP.
By doing more work on the client side, you can make what's called a single page application, where using javascript addons such as backbone.js for Model/View/Controller and Bootstrap.js for good looking responsive user interface.
The Arduino doesn't need to concern itself with the client side application, just send the data when asked for it, which can be adjusted to go pretty fast.
For even faster data updates between an Arduino system and web based application, then using TCP sockets might the way to go, but you need a good understanding of all things 'Ethernet and TCP'.
Anyhow, you provide very little information in terms of the code on your Arduino and the actual data path to any connected client.
I'm guessing the analogue sensor value is stored and used by the web server code you have on your Arduino, and it is this value that is sent to the client when a HTTP connection is made, is that correct ?
Paul - VK7KPA