I am very new to beagleboard and doing my curriculum
project in this board.
welcome to the list.
I tried to boot ubuntu from SD card. but it does not detect
the os and no os in NAND memory.
Please post the messages written to the serial console.
basic commands like boot are not working, it says like unknown
command.
pls help me to get through this.
You have to be more specific to get help. What board revision do you
have? What SD card image do you use? How is your board powered? The more
information nicely presented the better.