PURPOSE: To obtain a storage device which suitably stores video information whose responsiveness in fixed with at fixed speed is important by securing uniform responsiveness as to total access.
CONSTITUTION: A time control part 32 is provided in an I/O processor 3 between a main processor 1 and a storage device 4. Then a storage area 321 for a permitted time span is provided on the time control part 32. When optional one task among plural tasks of the main processor 1 gains successive access, one of divided time spans is assigned and only access from a permitted task is allowed in the time span. When the residual time spans can not be assigned, the task is informed that access is disabled. Consequently, the instantaneous response of access can be secured for all the tasks assigned to the time spans and real- time access is stably gained.
KISHIGAMI JUNICHI
ISHIKAWA ATSUSHI
KOTANI HISAYA
