Patent ID: 7664923

Claim:
A method for updating software stored in a flash memory of a single independent portable device by using an updating process with plural steps, the method comprising the steps of: updating the software while storing log data indicating results of implementation of each step of the updating process in a journaling area allocated in the flash memory of the portable device; whenever each step of the updating process is completed, copying the log data stored in the journaling area into a first backup journaling area allocated in the flash memory of the portable device and storing log data indicating copying results in a second backup journaling area allocated in the flash memory of the portable device, wherein said flash memory is a NAND-type flash memory; determining whether the journaling area is normal when it is confirmed during booting that the updating process has been suspended; resuming the suspended updating process by referring to the log data stored in the journaling area when the journaling area is determined to be normal; copying the data stored in the first backup journaling area into the journaling area by referring to the log data stored in the second backup journaling area when the journaling area is determined to be abnormal; and resuming the suspended updating process by referring to the log data copied into the journaling area.