Patent ID: 8100496

Claim:
A printer comprising: a printer main body having a data signal line capable of communicating data signals; and a plurality of liquid containers to be detachably mounted on the printer main body and to be commonly connected to the data signal line, wherein each of the plurality of liquid containers includes a light-emitting unit, a control unit that controls a state of the light-emitting unit; and a memory that stores color information of liquid contained in each of the plurality of liquid containers, wherein each of the plurality of liquid containers receives, from the printer main body through the data signal line, the data signals including a plurality of command groups each combining color information and a control code for controlling the state of the light-emitting unit, and wherein, in a case where a liquid container of the plurality of liquid containers receives color information that coincides with the color information stored in the memory, the control unit controls the state of the light-emitting unit in accordance with the control code included in the command group having the color information and performs switching between an ON state and an OFF state of the light-emitting unit during an inactive period during which the data signals are not input from the printer main body to the plurality of liquid containers.