Portable data storage device and method of accessing data thereof

A method of accessing data via portable data storage device, comprising the steps of:

• (a) executing predetermined applications or drivers in a segment I of a memory of said portable data storage device to set up said applications or drivers in a corresponding external electronic apparatus;
• (b) verifying whether the electronic apparatus has an operating system with different levels of limits to user authority;
• (c) verifying whether an operator logs on the operating system using a “user” account when a result from the step (b) is yes, so as to verify the operator's identity;
• (d) allowing said electronic apparatus to use instructions of a higher level to directly access data in a hidden segment III of the memory of said portable data storage device when the result from the step (b) is no, or when the result from the step (c) is no to indicate the operator logs on the operating system using an administrator account level;
• (e) allowing applications stored in the segment I of the memory of said portable data storage device to load specific read instructions for a read/write level application interface into a public segment II of the memory of said portable data storage device;
• (f) using firmware to check and execute the read instructions in said segment II, in order to move client data stored in said hidden segment III to said public segment II;
• (g) allowing the applications stored in the segment I of the memory of said portable data storage device to read out data in the segment II, so as to output the client data in said public segment II to said external electronic apparatus;
• (h) allowing the applications stored in the segment I of the memory of said portable data storage device to load specific write instructions for the read/write level application interface into said public segment II, and temporarily storing incoming data from said external electronic apparatus in said segment II;
• and
• (i) using firmware to check and execute instructions in said public segment II, so as to write the incoming data stored in said public segment II into said hidden segment III.