Logical-to-physical address translation for a removable data storage device

A method for making memory more reliable and for accessing encrypted data stored in a removable storage device by translating a logical memory address provided by a host digital device to a physical memory address in the removable storage device, the method comprising:

• receiving a logical memory address from the host digital device, the logical memory address corresponding to a location of encrypted data stored on the removable storage device;
• determining a logical zone of memory on the removable storage device, the logical zone corresponding to the logical memory address;
• determining a local address within the logical zone of memory on the removable storage device, the local address within the logical zone corresponding to the logical memory address;
• creating a lookup table in random access memory coupled with a processor of the removable storage device based on memory map data stored in flash memory corresponding to the logical zone, the flash memory coupled with the processor;
• determining a physical memory address corresponding to the local address within the logical zone by accessing the lookup table in random access memory;
• determining a decryption key corresponding to the encrypted data stored at the physical memory address;
• decrypting the encrypted data stored at the physical memory address using at least the decryption key to produce decrypted data;
• and
• transmitting the decrypted data to the host digital device;
• wherein creating the lookup table in random access memory is responsive to determining that a lookup table previously stored in the flash memory corresponding to the logical zone is invalid.

A method for making memory more reliable and for accessing encrypted data stored in a removable storage device by translating a logical memory address provided by a host digital device to a physical memory address in the removable storage device, the method comprising:

• receiving a logical memory address from the host digital device, the logical memory address corresponding to a location of encrypted data stored on the removable storage device;
• determining a logical zone of memory on the removable storage device, the logical zone corresponding to the logical memory address;
• determining a local address within the logical zone of memory on the removable storage device, the local address within the logical zone corresponding to the logical memory address;
• creating a lookup table in random access memory coupled with a processor of the removable storage device based on memory map data stored in flash memory corresponding to the logical zone, the flash memory coupled with the processor;
• determining a physical memory address corresponding to the local address within the logical zone by accessing the lookup table in random access memory;
• determining a decryption key corresponding to the encrypted data stored at the physical memory address;
• decrypting the encrypted data stored at the physical memory address using at least the decryption key to produce decrypted data;
• and
• transmitting the decrypted data to the host digital device;
• wherein the physical memory address corresponding to the local address within the logical zone may correspond to a different flash memory chip than a physical memory address corresponding to a different local address within the logical zone.

A removable storage device configured for making memory more reliable comprising:

• flash memory including a plurality of non-volatile memory storage blocks;
• a processor coupled with the flash memory and configured to read data from and write data to the non-volatile memory storage blocks;
• a communications interface coupled with the processor and configured to communicate the data to and from a host digital device;
• a memory having stored thereon firmware executable by the processor to perform a method comprising:
• receiving a logical memory address from the host digital device, the logical memory address corresponding to a location of encrypted data stored on the removable storage device;
• determining a logical zone of memory on the removable storage device, the logical zone corresponding to the logical memory address;
• determining a local address within the logical zone of memory on the removable storage device, the local address within the logical zone corresponding to the logical memory address;
• creating a lookup table in random access memory coupled with a processor of the removable storage device based on memory map data stored in flash memory corresponding to the logical zone, the flash memory coupled with the processor;
• determining a physical memory address corresponding to the local address within the logical zone by accessing the lookup table in random access memory;
• determining a decryption key corresponding to the encrypted data stored at the physical memory address;
• decrypting the encrypted data stored at the physical memory address using at least the decryption key to produce decrypted data;
• and
• transmitting the decrypted data to the host digital device;
• wherein creating the lookup table in random access memory is responsive to determining that a lookup table previously created in the random access memory corresponds to a different logical zone than the logical zone corresponding to the logical address.