The Arduino Ethernet Shield allows an Arduino board to connect to the Internet. It is based on Ethernet chip Wiznet W5100. The Wiznet W5100 provides a network library (IP) that supports both TCP and UDP. Up to four simultaneous socket connections are allowed. Use the Ethernet library to write programs that connect to the Internet through the shield.
Arduino Ethernet Shield - Get your Arduino on the Internet!
Want your Arduino to check email? How about sending a Twitter (which can then be easily forwarded to a phone via SMS)? Or grabbing data from a website? There are so many possibilities for projects that connect to the Internet to share data (for instance, Pachube), now there's an easy way to do it with an Arduino. All of the TCP / IP stack wizardry is done for you in the module so its super easy to connect to any server.
The Arduino Ethernet shield has a standard RJ45 connection, and connects to the Arduino board through wire-wraps. This maintains the positioning of the pins intact and allows another shield to be added to the stack if desired. The reset button on the shield applies to both the W5100 and the Arduino board.
The Arduino uses digital pins the 10, 11, 12 and 13 (SPI) to communicate with the W5100 on the Ethernet shield. These pins cannot be used for other inputs or outputs.
The shield contains some network status LEDs:
- PWR: indicates that the Arduino board and the shield are on
- LINK: indicates the presence of a network and flashes when the shield transmits or receives data
- FULLD: indicates that the connection is full duplex
- 100M: indicates the presence of a connection of 100 MB/s (as opposed to 10 MB/s)
- RX: flashes when the shield receives information
- TX: flashes when the shield sends information
- COLL: blinks when collisions are detected on the network
The Arduino Ethernet shield is a module capable of opening connections to other servers on the Internet or function as a mini standalone server for web pages and does not require any additional equipment to accomplish this.
