Message display system for programmable controller

Claim 1

A message display apparatus for a programmable controller (PC) for displaying a message on a display screen while the PC is in operation, comprising: first message storing means for storing a plurality of different languages in a plurality of respective language storing areas, each of said language storing areas storing a plurality of messages in a language different from that of the other said language storing areas, said messages having the same meaning in the different languages being stored at addresses having a sequence corresponding to one another; second message storing means for storing a single language of said plurality of different languages to which only messages of said single language are transferred from said first message storing means and are stored at addresses having a sequence corresponding to the messages stored in a respective said language storing area of said first message storing means; message transfer means for transferring said messages of the single language based on a preset parameter, from said first message storing means to said second message storing means when power is supplied to said PC; message selection means for designating a message desired to be displayed on said display screen while said PC is in operation by an address determined to correspond to the meaning of said desired message in the second message storing means; and message display means for fetching the desired message at said address determined by said message selection means from said second message storing means and displaying said fetched message on said display screen.