Equipping Arduino with a powerful Web server thanks to the Wi-Fi Shield. We’ll show you today how to use the WiFi shield and its libraries to turn Arduino into a Web Server; in addition, we are going to use the I/O Expander shield to provide more input and outputs to the platform. We will describe how to handle the specific library to use the WiFi shield as a WEB client for a public website that will collect data coming from sensors. The Arduino-based WEB server can be accessed using a normal browser, displaying sensors values or activating outputs. In the examples provided with the library, there is already a code sketch that shows how to create a WEB server. The shortcoming of this example, however, is that the functions used only allow you to build and load the entire web page, including the values to be shown.
If you need to check the updated values, you are forced to refresh the page manually. Besides, the activation of a digital or PWM output is made by posting values through a “web form”, which returns the “Refreshed” page. I/O Expander WEB Server.