Add more Digital Inputs and Outputs to your Arduino (IOExtension Module with library)

A lot of Dev Boards like Arduino, STM, ChipKit etc (Even micro computers like Raspberry Pi) have a limited number of Digital input and output pins, which is a serious problem for the makers while creating them projects, especially when the Dev Board should be connected to an important number of peripheric (Exemple: the 5x5x5 LED Cube where you need to control more than 100 LED). Our goal is to satisfy the users desires by making a Hardware and Software solution to add more Digital I/O pins to your Dev Boards. The IOExtension module is based on four shift registers (74HC595) to provide 16 Digital Inputs and 16 Digital Outputs, you will need only four pins in your Dev Board to control the module, plus the Vcc and the Gnd pins. The use of this module is so handy because the MEGA DAS community developed an Arduino software library to grant you using the module with a minimum code instructions.”

Link