Valid addresses range is from 0000h to FDFFh
 and from 10000h to 1007Fh. 
 The address range from FDFEh to FDFFh are
 reserved for 'Write/Erase Lock Byte' and
 'Read Lock Byte'.
 The address range from FE00h to FFFFh are
 reserved for factory use.
 The address range from 10000h to 1007Fh are
 locked only if all blocks are locked.