Stylus and controller

A controller of a display device configured to perform a stylus detection operation in each of N (N>1) second periods arranged within a display cycle, which is a cycle of display operation, wherein

• after the stylus is detected by the detection operation, the controller transmits, once within the display cycle, a second command that identifies data to be transmitted by the stylus using the second period, and
• before the stylus is detected by the detection operation, the controller transmits, a plurality of times within the display cycle, a first command including type identification information that identifies a type of the display device.

A stylus for use with a controller of a display device, the controller configured to perform a stylus detection operation in each of N (N>1) second periods arranged within a display cycle, which is a cycle of display operation, wherein

• the stylus transmits a position signal in response to reception, from the controller, of a first command including type identification information that identifies a type of the display device, and
• the stylus transmits a data signal in response to reception, from the controller, of a second command that identifies data to be transmitted using the second period, the data signal including the data identified by the second command.

A controller of an in-cell type liquid crystal display device, the controller having first and second electrodes that intersect each other, supplying a pixel driving voltage to the first electrodes during a pixel driving period, and detecting a stylus position using the first and second electrodes during a stylus detection period different from the pixel driving period, wherein

• the controller transmits, using the second electrodes, a command requesting a transmission of a downlink signal to the stylus, and
• the controller detects, using the first and second electrodes, the downlink signal transmitted from the stylus in response to the command, and detects the stylus position based on the detected downlink signal.