A storage includes a first area in which an own device program is stored and a second area in which an other device program is stored at factory shipment. A data processor executes data processing with the other device based on the own device program. A version getter gets the version of the other device program stored in the other device. When the version of the other device program got from the other device satisfies a predetermined condition, a program transmitter transmits the other device program stored in the second area to the other device to cause the other device to update the other device program stored in the other device. A program updater temporarily stores an own device update program input from outside in the second area in place of the other device program and updates the own device program stored in the first area.