Patent ID: 8351356

Claim:
A data communication system including first and second devices that transmit and receive target data for processing via first and second channels connecting the first and second devices, the transmission and reception being performed by switching between full-duplex communication and half-duplex communication, wherein the first device includes: a first interface unit connected to the first and second channels; a first transmission unit operable to transmit an instruction code to the second device via the first channel when the first device is on a data transmitting end in the half-duplex communication, the instruction code indicating switching from the half-duplex communication to the full-duplex communication; a first switch control unit operable to switch a configuration of the first interface unit from a configuration for transmitting data via the second channel to a configuration for receiving data via the second channel; and a first communication control unit operable to start transmitting and receiving the target data in the full-duplex communication, after the switching by the first switch control unit is completed and a response code indicating completion of switching to the full-duplex communication is received from the second device via the second channel, and the second device includes: a second interface unit connected to the first and second channels; a second switch control unit operable to switch a configuration of the second interface unit from the configuration for receiving data via the second channel to the configuration for transmitting data via the second channel, upon receipt of the instruction code from the first device via the first channel; a second transmission unit operable to transmit the response code to the first device via the second channel, upon completion of the switching by the second switch control unit; and a second communication control unit operable to start transmitting and receiving the target data in the full-duplex communication, upon transmission of the response code by the second transmission unit.