The library code is mostly independent of processor used, however the original target platform is an Arduino Nano. The pins listed here and defined in the SC2_HardwareDefs.h header file are reserved (R) by the library. Spare pins are for use by any application Application (A) built on top of this library.

Pin	Use	Description
D0*	R	Hardware Serial Tx
D1*	R	Hardware Serial Rx
D2!	A	Spare
D3!~	A	Spare
D4	A	Spare
D5~	A	Spare
D6~	A	Spare
D7	A	Spare
D8	A	Spare
D9~	A	Spare
D11~*	A	Spare / Hardware SPI MOSI
D12*	A	Spare / Hardware SPI MISO
D13*	A	Spare / Hardware SPI SCK
A0	A	Spare
A1	A	Spare
A2	A	Spare
A3	A	Spare
A4*	A	Spare / Hardware I2C SDA
A5*	A	Spare / Hardware I2C SCL
A6	A	Spare / Nano Analog I/O only
A7	A	Spare / Nano Analog I/O only

(*) shared or comms bus pins, (~) hardware PWM pin, (!) external iRQ pin