Beagleboard booting problem

         I have revision B7 beagleboard.I have follwed MMC recovery
steps on beagle board.
I have used following command

OMAP3 # nand unlock
device 0 whole chip
nand_unlock: start: 00000000, length: 268435456!
NAND flash successfully unlocked
OMAP3 # nand erase 0 80000

NAND erase: device 0 offset 0x0, size 0x80000
Erasing at 0x60000 -- 100% complete.

I have also tried format mmc card and copy all files following
sequence on MMC.
After this steps I don't get anything on serial port(like command
prompt or boot up sequence)
How to resolve that?


Gaurang T