Patent ID: 7028127

Claim:
An operation method of a portable personal device having facilities for storing and playing digital contents by control from a computer through a serial or parallel cable, the method comprising the steps of: (a) receiving a format request command from the computer through a serial or parallel cable for formatting an internal memory installed in the portable personal device or an external memory in an external memory card inserted from outside the portable personal device; (b) sending from the portable personal device through a serial or parallel cable a signal indicating that the portable personal device is ready to format to the computer, when the portable personal device is ready to format; (c) receiving an execution command from the computer through a serial or parallel cable for executing the format request command received in the step (a); and (d) formatting the corresponding memory, when the execution command is received in the step (c), and then sending the result to the computer through a serial or parallel cable, wherein the structure of the transmission data which is received or sent in the steps (a) through (d) includes a start separator character for indicating a start of transmission data, information on length of the transmission data, an intermediate separator character for indicating a start of a command code or state information, the command code or state information, and an end separator character for indicating an end of transmission data.