Cyclone iii with SDR SDRAM

Hi,

This is my first FPGA project to start.

I am experimenting with my Cyclone iii based hardware having SDRAM for which I have attached the image files of my NIOS based sopc system.

I want to use this external SDRAM as main memory for my whole system.

For that I have put SDRAm contoller in my SOPC system as shown in figure.

SDRAm is: MT48LC8M8A2.

I have checked this configuration to run count_binary NIOS software application project on it, as per "NIOS II hardware development tutorial".

I can see the count binary in NIOS console of NIOS EDS and also respective changes in LED's status.

It means its is working very well.

To confirm that this application is running from SDRAM, I have turned off the 3.3V supply to SDRAM chip (using on board jumper ). And then I had reload the .sof file and run the count_binary though I am getting count in console and led's changing status !!!!!

How does it possible?

Does it run from on-chip memory even it is not configured in my SOPC system?

How do I know that this program is running from SDRAM itself not from on-chip memory?

Kindly guide me on this issue.

Thanks n regards.