DATA TRANSMISSION SYSTEM IN ELEVATOR CONTROLLER

摘要

PURPOSE: To simplify operations for originating redundant bits and for detecting errors so as to simplify circuit constitution by adding redundant bits only to such specific signals as directly affecting passenger safety. CONSTITUTION: In data transmission by use of a cable 4 between a control board 1 and the controller 3 of a car 2, redundant codes R2 -R0 are not computed and added to all the bits D7 -D0 of transmitted signal data at the data transmission side, but only redundant codes are added to a limited number of specific bits among them, e.g. control data and detection data relating to passenger safety, and are transmitted. At the data reception side, errors are detected only for the specific bits. Thus, computations for originating the redundant bits and for detecting errors become so simple as to be achieved even by program computations without the need for complex special logic circuits, resulting in significant simplification of circuit constitution.