i have executed the script that u have provided on Ubuntu it executed successfully and after connecting the switch to sd/mmc mode and connected the kit with hyperterminal it gives error
NAND: 512 MiB
MMC: davinci: 0
Bad block table found at page 262080, version 0x01
Bad block table found at page 262016, version 0x01
*** Warning - bad CRC, using default environment
In: serial
Out: serial
Err: serial
ARM Clock : 300000000 Hz
DDR Clock : 150000000 Hz
Net: Ethernet PHY: GENERIC @ 0x07
DaVinci-EMAC
Hit any key to stop autoboot: 0
reading boot.scr
** Unable to read "boot.scr" from mmc 0:1 **
reading uImage
** Unable to read "uImage" from mmc 0:1 **
Wrong Image Format for bootm command
ERROR: can't get kernel image!
U-Boot > <INTERRUPT>
U-Boot >
how to resolve it