Operation mode changing-over method and multiplex transmission apparatus for realizing the same

Abstract

A multiplex transmission apparatus is constructed with a plurality of nodes being connected to a multiplex transmission path. Each node has a multiplex transmission module for making multiplex communication with another node, a reception circuit connected to the multiplex transmission, and a micro-controller. The multiplex transmission apparatus has as its operation mode a multiplex communication mode in which each node performs its multiplex transmission and a sleep mode in which a multiplex transmission module is kept inoperative. When the reception circuit receives a seizing signal for changing over the operation mode from the sleep mode to the multiplex communication mode, from another node via the multiplex transmission path, a mode changing-over portion a micro-controller has changes over the operation mode from the sleep mode to the multiplex communication mode according to the seizing signal that has been received by the reception circuit, to thereby cause the multiplex transmission module to operate in the multiplex communication mode. A reception control portion in the micro-controller causes the reception circuit to makes its “off” operation immediately after transfer to the multiplex communication mode.