Altera Nios Development Board Stratix II Edition - Manual (Page 9)

Altera Corporation Reference Manual 1–3
May 2007 Nios Development Board Stratix II Edition
Overview
In the course of development, you might overwrite or erase the flash
memory space containing the default reference design. Altera provides
the flash image for the default reference design so you can return the
board to its default state. Refer to Appendix A: Restoring the Factory
Configuration for more information.