I2C connector pinout

For the interconnect between I2C masters and the I2C expansion boards BitWizard uses a 4-pin I2C cable.

The connector is laid out as follows:

pin	function	remark
1	GND	Power Ground
2	SDA	Serial I2C Data
3	SCK	Serial I2C Clock
4	VCC	Power 5V.

Connecting the BitWizard boards to an Arduino

pin	function	arduino pin	Arduino Mega
1	GND	GND	GND
2	SDA	A4 (Analog input 4)	Digital 20
3	SCK	A5 (analog input 5)	Digital 21
4	VCC	VCC	VCC

You could use other pins, but then you have to make a software I2C implementation. This is not too difficult, but might be neccesary if something else is already on the I2C pins.

Example connection to rpi_serial

i2c_lcd connected to rpi_serial