Communication device for automatic vending machine

摘要

A communication device for an automatic vending machine includes, a main control unit that initializes each unit in accordance with a result of decoding an initialization order from ROM, and transmits first to third control data in the form of telegraphic message through a data input/output line to a plurality of button control units one by one. The plural button control units are set to have or not to have a transmission right to the main control unit in accordance with a latch result of the first to third control data. The transmission right of the terminal control units can be set by the main control unit as the automatic vending machine carries a communication between the main control unit and the terminal control unit by contention type protocol.