1. A semiconductor integrated circuit device for use with a first processing unit and a display device, the semiconductor integrated circuit device comprising: a central processing unit; a first interface circuit; and a second interface circuit; wherein the semiconductor integrated circuit device has an operating mode and a standby mode as an operation mode thereof and operates in one of an operating mode and a standby mode, wherein the semiconductor integrated circuit device further includes: a first signal route which is from the first processing unit to the display device via the first interface unit, the central processing unit and the second interface unit; and a second signal route which is from the first processing unit to the display device via the second interface unit, wherein, in the operating mode, the semiconductor integrated circuit device receives first data signals from the first processing unit, the central processing unit conducts processing based on the first data signals from the first processing unit and is operable to provide second data signals from the semiconductor integrated circuit device to the display device via the first signal route, and wherein, in the standby mode, the second interface unit and the second signal route are provided with a power supply, and third data signals from the first processing unit are directly provided to the display device via the second signal route, wherein the third data signals include display data for the display device, and wherein the standby mode is a lower consumption state than the operating mode.