A system includes: a first device; a second device connected to the first device via a transmission line; and control devices that are coupled to the first and second devices and control transmission and reception of a data signal and a timing signal between the first device and the second device, wherein the first device: determines a combination of phases with which a range of a voltage of determination as to whether the data signal is acquired is wider than a range of a voltage in which the data signal is acquired in other combinations of phases in information including combinations of phases in which a phase of the timing signal is specified for each data line in the transmission line, when the second device is operated according to the combinations of phases based on the information; and controls the second device based on the combination of the phases.