Patent ID: 8082375

Claim:
A data communication system comprising: a host; a device; a control line connecting the host and the device so as to convey a control signal; a clock line connecting the host and the device so as to convey a clock; a data line connecting the host and the device so as to convey data, the data line receiving a data read-in request signal from the device and sending the data read-in request signal to the host when the control signal is at a first level, and the data read-in request signal requesting reading-in of the data by the host; and a data line control circuit controlling the data line so that outputting of the data read-in request signal to the data line is disabled in response to first command data being inputted from the host to the device through the data line in synchronization with the clock and that the outputting of the data read-in request signal to the data line is enabled in response to second command data being inputted from the host to the device through the data line in synchronization with the clock.