In a device, in which a master that requires access at a predetermined rate and a processor that requires responsiveness to an access request access a shared memory, responsiveness to the access request of the processor is improved while the access of the master at the predetermined rate is guaranteed, compared to conventional technologies. When the master has a resource available for accessing the shared memory, the master accesses the shared memory at the predetermined rate or above. When the access is executed at the predetermined rate or above, the processor accesses the shared memory by using a resource that was originally allocated to the master.