Patent ID: 7904896

Claim:
A system with a first memory for rewriting a first application program stored in the first memory into a second application program, the system comprising: an external device configured to store therein the second application program and configured to carry out any one of: a first procedure to thereby: send a rewrite control program stored in the external device as write target data; send an identifier identifying that data subsequent to the sending of the identifier represents the second application program; and send, subsequent to the sending of the identifier, the second application program as the write target data; and a second procedure to thereby send the identifier identifying that data subsequent to the sending of the identifier represents the second application program; and send, subsequent to the sending of the identifier, the second application program as the write target data without sending the rewrite control program, the rewrite control program, which is previously stored, allowing the system to rewrite the first application program into the second application program; and a control unit having a second memory and communicably coupled to the external device when rewriting the first application program into the second application program, the control unit comprising: a determining unit configured to determine whether to receive the identifier sent from the external device; a first identification unit configured to store, in the second memory, the write target data sent from the external device as the rewrite control program when determining that the identifier has not been received; and a second identification unit configured to, when determining that the identifier has been received, identify that the write target data sent from the external device is the second application program, and rewrite the first application program into the second application program sent from the external device as the write target data.