| 摘要 |
PURPOSE:To exclude a synchronizing circuit, a filter device, etc., by controlling plural ON/OFF signals supplied from the centralized controller side after comparing them with the reference value through a comparator provided at the terminal device side. CONSTITUTION:A centralized controller 1 contains plural channels 3a, 3b...3l, and the DC signals of different values are set to these channels respectively via switches 4a, 4b...4l. A transmission line 6 is connected to a terminal resistance 7 at the terminal device side 2 as well as to comparators 8a, 8b...8l constituting a channel discriminating circuit 8. These comparators are set to correspond to the channels 3a, 3b...3l of the controller 1 to compare the ON/OFF signals with the reference voltage in accordance with each channel. Then each channel is discriminated for output. |
