The NAND architecture used by SanDisk and other card vendors currently has Erase Block sizes of (32) or (64) 512 byte blocks, depending on card capacity. In order to re-write a single 512 byte block, all other blocks belonging to the same Erase Block will be simultaneously erased and need to be rewritten. The microSD card manages this function without the requirement of system drivers unlike raw flash memory.

For the high-lite...they say drivers are not required. They are required....they're devised within.

  If it has segment management for space reclaim, someones IP is in there doing it.

 doni