In response to receiving process-request information from an external device after starting operation by second power, a communication controller is configured to perform: a first supplying process of controlling a second power supply to supply the second power to a first communication node; a first data communication process of performing data communication with the first communication node after starting the first supplying process, wherein the first data communication process includes receiving process-related information from the first communication node; a determining process of, after finishing the first data communication process, determining whether data communication with a second communication node is necessary, based on the process-request information and on the process-related information; and a second supplying process of controlling the second power supply to supply the second power to the second communication node, in response to determining in the determining process that data communication with the second communication node is necessary.