General questions about memories, configuration and FPGA systems.

The byte enables are there so you can have interfaces that are 16 or 32 bit wide and still retain the ability to address individual bytes.

NIOS has a 32 bit wide master interface. When it executes an 8 bit store instruction, it will automatically set the correct byte enables, along with the target address.

If you only have an 8 bit or 16 bit wide memory bus, the memory controller shall also have an 8 or 16 bit wide slave interface.

In this case, the Avalon fabric will make the adaptation between NIOS' 32 bit interface and the memory controller's 8 or 16 bit interface and everything will work correctly.

What dsl was trying to convey is that the fabric will handle the conversion in less than 100% efficient manner.