The ENC28J60 is a stand alone Ethernet controller with SPI interface in 28 pin SOIC package. It features onboard MAC & PHY, 8Kbytes of buffer RAM and SPI serial interface. The ENC28J60-I/SO is designed to serve as an Ethernet network interface for any controller equipped with SPI. It meets all of IEEE 802.3 specifications. This Ethernet controller incorporates a number of packet filtering schemes to limit incoming packets. It also provides an internal DMA module for fast data throughput and hardware assisted checksum calculation which is used in various network protocols. Communication with host controller is implemented via an interrupt pin and SPI with clock rates of up to 20MHz. Two dedicated pins are used for LED link and network activity indication.