PROGRAM UPDATE METHOD AND PROGRAM UPDATE DEVICE

PROBLEM TO BE SOLVED: To provide a program update device capable of upgrading firmware without suspending a function of firmware. SOLUTION: The program update device includes: difference information setting means 13 for extracting difference information based on a first map file and a second map file, and setting it in difference information storage means 41; pseudo access means 42 for specifying an address of data in a second main storage area 1b corresponding to a specified address and writing the data in the second main storage area 1b, based on the difference information when central processing means 30 specifies the address and writes data in a first main storage area 1a; determination means 14 for determining a match of each piece of data in the first main storage area 1a with each piece of data in the second main storage area 1b corresponding to each piece of data in the first main storage area 1a; and operation switching means 15 for switching the operation from the first main storage means 10a to the second main storage means 10b. COPYRIGHT: (C)2010,JPO&INPIT