In sopc builder when you edit the options for your NIOS II processor, you specify which memory in your system will be used for the reset and exception addresses. When the NIOS boots, it will begin executing code at the reset address. This memory can literally contain any code whatsoever.
Now obviously the address you set the reset address to needs to contain your boot code. Typically this is flash memory which contains a boot loader that will copy your program into RAM and then jump to the program code and continue execution from there.
So. In SOPC builder, set the reset address for the NIOS appropriately.
Now in the NIOS II IDE you will create a system library for your software application. In the system library you will specify where the different memory sections of the program will be located. Typically you will set all of these sections to some RAM (SRAM, DDR, DDR2, onchip memory) that will be the memory that you want your program to execute from.
When you build your project, the NIOS II IDE will create a memory initialization file or a flash programming file for your boot ROM. If your boot memory is flash, you can use the NIOS II flash programmer to program the boot code into flash.
Please get as much info as you can from the following sources:
http://www.altera.com/literature/lit-nio2.jsp http://www.altera.com/literature/hb/nios2/edh_ed_handbook.pdf Jake
