| 摘要 |
PURPOSE:To realize an emergent interruption with a simple and low-cost device, by detecting the fact that the carrier presence signal of a slave station has been produced when a command signal for calling a slave station is not delivered to the slave station. CONSTITUTION:An emergent interruption signal 12 is delivered from an emergent information detecting circuit 5 of a slave station 18, and a carrier transmission command 11 is produced. Thus a carrier wave is transmitted from a transmitter 9, and a carrier wave detector 21 for the slave station detects the carrier wave to deliver a carrier wave presence signal 26 for the slave station. An interruption request signal 32 to a slave station is supplied to a control device 33 for calling the slave station through an AND gate 23, and the device 33 produces a command signal for calling the slave station. And a control device slave station 7 of a slave station 18 is called at a master station 1. As a result, an interruption memory set signal 8 is supplied to the circuit 5, and the signal 12 is reset. |
