Valid addresses range is from 0000h
 to 1DFFh and from 2000h to 207Fh.
 The address range from 1DFEh to 1DFFh
 are reserved for Write/Erase Lock Byte
 and Read Lock Byte.
 The 512 bytes from addresses
 1E00h to 1FFFh are reserved for factory use.
 The address range from 2000h to 207Fh
 are locked only if all other blocks
 are locked.