1. A display control device for controlling a display of a display device responding to display processing from a plurality of processing units, comprising: a display controlling program that controls the display device in response to at least one processing unit, comprising: receiving a request from one processing unit to acquire one of predefined display areas; and determining whether to provide an authorization to acquire one of a plurality of predefined display areas in response to an acquisition request from the one processing unit to acquire the one of predefined display areas, wherein, when a plurality of requests to acquire the same one of predefined display areas from a plurality of processing units are received, the authorization is provided to a single processing unit that made one of the requests to acquire the same one of predefined display areas, the display device being instructed by a processor based on the display controlling program, and a memory being connected to the processor to store the display controlling program, wherein, when an acquisition request for the same one of predefined display areas is received from processing units, the processor instructs the display device based on the display controlling program.