Girish 
Hi, I have compiled zImage and write into NAND Flash and test with "b" boot from ram in Supervivi and it works fine but when i put switch S2 to NAND and reset the board, board not showing any display and nothing in the serial port. But if i restore my default flash provided by FriendlyARM and press reset in NAND mode then board gets autoboot in NAND mode. What setting i am missing any help is appreciable Thanks in advance Regards Girish