1. Arduino and the Web

2. The Ethernet Shield
This shield allows the Arduino to be plugged into a network and ultimately talk to the web
The Ethernet library takes care of assigning an IP address and offers functions to talk to the web
Search the web for more details on how the web works as that is out of the scope of this course
DHCP, DNS, IP, GET, POST are some key words

3. The Actual Shield

4. Sandbox Network
Since Lehigh’s network is quite complex, it is easier to create our own personal network to wire the shield to
Take an ordinary router and plug the WAN/Internet port into the Ethernet jack in the lab
Plug the Arduino shield into one of the open LAN ports
Connect your laptop to this network too to test if internet is up and running
This will help eliminate errors when developing for the web with Arduino

5. Router Wiring

6. Arduino Shield Stack

7. Method to our Madness
You will notice small dashes next to some of the pins on the shield
These pins are the ones used for communication between the Arduino and the Ethernet chip
This is why we left these ports open during the development of the chamber
Remember the 6 P’s of success
Prior Planning Prevents Piss Poor Perfomance

8. The Test
To test that we can communication with the web run the Ethernet example
Examples->Ethernet->Web Client
In Arduino there is an error in the example that will prevent the Arduino from downloading from the web
They are using the wrong IP address for Google!
Change the Server ip to server(74,125,224,72) and give it a go!
A sample of the serial output is on the next page
Be sure to set the serial console to 9600 from the we are using for our chamber or else you will see gibberish displayed

9. Serial Console