Unlike nearly every other aspect of embedded system programming, getting it wrong with FLASH devices can render your target system useless. Most targets have a boot loader in the FLASH. Without this boot loader the target will obviously not boot. So before starting to play with this library its worth investigating a few things. How do you recover your target if you delete the boot loader? Do you have the necessary JTAG cable? Or is specialist hardware needed? Is it even possible to recover the target boards or must it be thrown into the rubbish bin? How does killing the board affect your project schedule?