szangvil:
Sound more simple to buy the chip with a bootloader already burned in.But how can I be sure that the chip I buy (from mouser)has a bootloader?
I don't think mouser sells them with a bootloader, but I could be wrong. If a given vendor has that option (bootloader preinstalled) it will clearly state so in the description. The ATMEL folks don't manufacture them with a bootloader so it's only vendors that can add that option.
Lefty