How to communicate with the GPIO (JP1) using the NIOS II in C?

Good morning everyone! In my dissertation project I am using a ALTERA DE2 board. My goal is integrating some presence sensors through Expansion JP1 parallel port (GPIO) so that I can get information from certain pins that are connected to sensors, to help in decision-making process of my application. Does anyone know how I can do this using the NIOS II with the C programming language?