Datasheet

'Classic' Arduino Wiring:

On pre-R3 Arduinos, the I2C pins are:

SDA = Analog 4

SCL = Analog 5

For the Mega

SDA = Digital 20

SCL = Digital 21

R3 and Later Arduino Wiring:

Although the 'classic' wiring will still work, All R3 and

later Arduinos (including Mega, Due and Leonardo) have

SDA and SCL pins on the extended header next to AREF

for compatibility.

Wiring for SPI:

The SPI interface requires 4 wires (in addition to VCC and Ground).

SPI Wiring:

The library uses "software SPI" so the choice of pins is a

little more flexible. What we show here is compatible

with the example code included with the library:

CS = Digital 4

SAO = Digital 5

SDA = Digital 6

SCL = Digital 7