The Arduino Ethernet board is based on ATmega328microcontroller. It has 14 digital input/output pins, 6 analog inputs, a 16 MHz crystal oscillator, a RJ45 connection, a power jack, an ICSP header, and a reset button.
Note: Pins 10, 11, 12 and 13 are reserved for interfacing with the Ethernet module and should not be used otherwise. This reduces the number of available pins to 9, with 4 available as PWM outputs.
It does not have an onboard USB-to-serial driver chip, but has a Wiznet Ethernet interface. The board can be programmed through 6-pin serial programming header or with an external ISP programmer.To upload sketches using 6-pin serial programming header, it would require a USB Serial adapter (part no. ) or FTDI USB cables (part no. ).
An onboard micro SD card reader, which can be used to store files for serving over the network, is accessible through the SD Library. Pin 10 is reserved for the Wiznet interface; SS for the SD card is on Pin 4.
The board can also be powered via an external ac-dc power adapter/ battery. The recommended range is 7 to 12 volts.The adapter can be connected by plugging a 2.1mm center-positive plug into the board's power jack. Leads from a battery can be inserted in the Gnd and Vin pin headers of the POWER connector.
The board can also be powered using a FTDI cable/USB Serial adapter.