The Arduino Ethernet Shield gives you an easy way to get your Arduino Online. It uses Arduino official Wzinet W5100 ethernet chip (not cheap ENC28J60) And it is directly supported by Arduino official Ethernet Library.
The Wiznet W5100 provides a network (IP) stack capable of both TCP and UDP. It supports up to four simultaneous socket connections. Use the Ethernet library to write sketches which connect to the internet using the shield.
The SD card is not supported in this version.
Arduino Duemilanove (168 or 328) (Compatible)
Arduino UNO (Compatible)
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