A serial communication method between a device and a host, in which the device reports touch data including a coordinate of a detected active stylus to a host. The host issues a write command that includes data indicating a request of a descriptor, to the device. After the device performs a predetermined process for the write command, the device transmits an interrupt to the host. The host requests the device to transmit the touch data, triggered by the host detecting the interrupt. The device transmits the descriptor in response to a request for transmission of the touch data. The method can enable a sensor controller to notify the host of the descriptor even in a case where communication is performed between the sensor controller and a host processor in accordance with a standard that does not provide a command usable for the device to notify the host of the descriptor.