SOPC & Nios II EDS常见问题集锦（持续更新）

1、问：新建工程时报错对话框“ Failed to execute：./creat-this-app --no-make ”

     答：以管理员身份运行Nios II EDS

2、"Warning: cpu: The address range of the slaves connected to the NIOS 2 instruction master exceeds 28 bits. Attempts to call function across 28 bit boundary is not supported by GCC and will result in linker errors"

     答：http://www.alteraforum.com/forum/showthread.php?t=31689

This is because one of the slaves you connected to instruction master has been mapped to address 0x1000 0000 or above.
Locking base address is the correct procedure. You must have: base_address + slave range < 0x1000 0000

Connection to instruction master is mandatory if your memory slave is supposed to store code, since Nios use this bus connection to fetch instructions into the cpu for execution.
If you use a memory device uniquely for data storage, then only connection to data master is required. 
Separate instruction and data paths are convenient because cpu can fetch both an instruction and data in the same cycle, thus increasing performance compared to a single bus machine.