Saving data in to an external SD-CARD on DE0-NANO BOARD

Hello, I am Student from a University beginner in FPGAs, and I want to use a Nios II that uses a Altera DE0_nano Board to do some operations and save the results from the g_sensor (X,Y,Z...numerical values).

I have connect an external SD card in order to save the data from the g_sensor(adxl 345) into SD-card.

If someone knows how save values in the external SD card, I really appreciate your help, if you help send me.