Is it possible to increase the Arduino's input and output pins? I am undergoing a BSc (Hons) Degree in Computer Science and working on an Arduino project.

I am using the Arduino Mega and even though this microprocessor has plenty of input and output pins I am running out.

In the event that there are no more I/O pins available for me to make use of, and I am also referring to both analog and digital pins, is it possible to increase them?

I did some research, however the solutions are too vague... One of the suggestions was to use one or more of the following: 74HC595 8-Bit Shift Register DIP-16.



I am good at coding however when it comes to hardware sometimes I'll need some push.

Thanks a lot.
You could use an MCP23017 port expander to get 16 more pins. It communicates via I2C. The pins can be set as inputs, outputs, or inputs with pullups.

Adafruit has a library for the expander: https://github.com/adafruit/Adafruit-MCP23017-Arduino-Library

This is the datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/21952b.pdf

As an alternate solution, you could just add another Arduino Mega to your project, and have them both communicate via serial. You could set up state machines on each one (like in Mr. Gammon's tutorials: http://www.gammon.com.au/statemachine) for fast communication. That way you could easily add an extra 52 pins to your project.