Patent ID: 8458409

Claim:
An access control apparatus that receives access requests from (i) one or more type-1 masters for each of which a maximum amount of resources used to access a memory within a unit period is preliminarily determined and (ii) a type-2 master different from the type-1 masters, and sequentially selects one of the access requests as an allowable access request, the access control apparatus comprising: a management unit operable to manage an amount of unused resources, the amount of unused resources being calculated, when each of the type-1 masters makes an access request within the unit period, by subtracting an amount of resources used by each of the type-1 masters having made the access request from the maximum amount of resources determined for each of the type-1 masters having made the access request, and a selection unit operable to, when one of the type-1 masters and the type-2 master make access requests within the unit period, select the access request made by the type-2 master as the allowable access request if a total amount of unused resources managed by the management unit is equal to or larger than an amount of resources to be used by the type-2 master, and select the access request made by the one of the type-1 masters as the allowable access request if the total amount of unused resources managed by the management unit is smaller than the amount of resources to be used by the type-2 master.