A paper floating detection apparatus is arranged at a conveyance path of a conveyance device which holds paper on a conveyance surface and conveys the paper in a conveyance direction while causing a surface of the paper to face a droplet ejection head. The processor, in response to the input detecting the information of the data item, may control the display screen to display one or more additional windows. The board to board connector receives a circuit board on the first mating face and a circuit board on the second mating face.