The Arduino Ethernet Shield 2 is an add-on board that allows an Arduino AVR controller board to connect to Ethernet/the Internet. In contains the Wiznet W5500 Ethernet chip, which provides a network (IP) stack that supports both TCP and UDP. The Arduino Ethernet Shield 2 supports up to eight simultaneous socket connections. Use the Ethernet 2 Library to write sketches (code) to connect to the Internet using the shield.
Any code written for the older Arduino Ethernet Shield still can be used on this new shield simply by altering two #include lines (see the Labs page link below for instructions).
The Ethernet shield connects to an Arduino board using long wire-wrap headers which extend through the shield. This keeps the pin layout intact and allows another shield to be stacked on top.
The Ethernet Shield 2 has a standard RJ-45 connection, with an integrated line transformer and Power-over-Ethernet enabled (a PoE module is not included).
There is an on-board microSD card slot which can be used to store files for serving over the network. It is compatible with the Arduino Uno and Mega (using the Ethernet library). The on-board microSD card reader is accessible through the SD Library. When working with this library, SS is on Pin 4.
The shield also includes a reset controller to ensure that the W5500 Ethernet module is properly re-set on power-up.
The current shield has through-holes for adding a Power-over-Ethernet (PoE) module designed to extract power from a conventional twisted pair Category 5 Ethernet cable.
Arduino communicates with both the W5500 and SD card using the SPI bus (through the ICSP header). This is on digital pins 11, 12, and 13 on the Uno and pins 50, 51, and 52 on the Mega. On both boards, pin 10 is used to select the W5500 and pin 4 for the SD card. These pins cannot be used for general I/O. On the Mega, the hardware SS pin (53) is not used to select either the W5500 or the SD card, but it must be kept as an output or the SPI interface won't work.
Note that because the W5500 and SD card share the SPI bus, only one can be active at a time. If you are using both peripherals in your program, this should be taken care of by the corresponding libraries. If you're not using one of the peripherals in your program, however, you'll need to deselect it explicitly. To do this with the SD card, set pin 4 as an output and write a High to it. For the W5500, set digital pin 10 as a High output.
The shield contains a number of informational LEDs: ON, LINK, FDX (full duplex mode), 100M (100Mbps connection), ACT (activity).
New to this version of the shield is a series of TinkerKit I/O and communication interfaces on the top side of the board (TWI x2, OUT6, OUT5, IN2, IN3).
Arduino Ethernet Shield 2 Resources
Note: This board is developed by Arduino.org — not Arduino.cc — thus it is recommended to use the IDE from Arduino.org.