Patent ID: 8522352

Claim:
A key device with external storage comprising a micro-controller unit and an off-chip mass storage that stores a software which is used to manage information in the key device by controlling operation of a firmware program when the software is executed in a host at runtime, wherein the micro-controller unit comprises a host interface module, a CPU, a key data storage module, a firmware program storage module which stores the firmware program and an off-chip mass storage interface module; the host interface module is adapted to connect the host with the key device; the micro-controller unit and the off-chip mass storage are connected via the off-chip mass storage interface module, wherein the firmware program storage module is adapted to store the firmware program of the key device; the firmware program is mainly adapted to realize communications between the key device and the host, analyze and process the information sent by the host, realize management of rights, perform input/output management for all memory sections, and encrypt and/or decrypt data, wherein controlling operation of the firmware program by the software is completed by the software specifying a path and a name of a preset program that is stored in the off-chip mass storage module, and the software executing the preset program in the host.