PURPOSE: To manage the kinds of main body system devices of different function version number with logical scan address(LSOA) files which are less in number than connected devices by switching over the logical scan address files to be referred to and making a logical scan.

CONSTITUTION: Function version number (1) supplied to a main body system device 1 are grouped by plural function version number (1a), (1b),... which are mutually different in scan address, and the logical scan address files (LSOA file) 20a, 20b,... are provided corresponding to the grouped function version number. When a service processor (SVP) 2 makes a logical scan on the main body system device 1, main body system device 1 of the same kind and the LSOA files 20a, 20b,... are made to correspond to each other with the function version V1 of the main body device and when the function version number V1 of the main body system device is larger than the number of grouped threshold version number XS, the LSOA files 20a, 20b,... corresponding to the function version number V1 are selected.