| 摘要 |
PURPOSE: To minimize wiring in a system by providing a display device for the labels of plural display shelves and a storage battery as the power source of a subordinate device installed at a distance from a central processing arithmetic unit. CONSTITUTION: A control circuit provides control over structure including an in-store processor(ISP) which is coupled with a modem 54 by an RS232C interface means and may be a personal computer 52. The modem 54 is coupled with an acoustic amplifier 56 and coupled with a transmission loop 58 from it, and the transmission loop 58 communicates with a receiving call or pickup coil 66 coupled with a display device 64 by a radio means. Then the subordinate device of the induction loop system which operates in the sound frequency band is supplied with electric power by a battery and not physically connected to a host device. Further, a reception device uses a coil for picking up a signal and this signal is amplified and inputted to the modem device, so that data sent out to the subordinate device first are restored. |
