Chetan Dadhaniya 
Dear Friends. I have Mini2440 card with 1Gib Nand Pre-Loaded with superboot. I have loaded u-boot.bin using minitools utility. When I reset board with S2 in NAND flash u-boot runs & it shows #mini2440 prompt. but Just after I "run dynenv set 40000" command & resets the board #mini2440 prompt does not comes again. I had tried loading u-boot using sd card also, but with same result. Please guys Point me where I am wrong? Thanks Chetan Dadhaniya