SEQUENCE PROGRAM, RECORDING MEDIUM WITH RECORDED SEQUENCE PROGRAM, PROGRAMMABLE CONTROLLER STORING SEQUENCE PROGRAM, AND SEQUENCE PROGRAM PROTECTION SUPPORT METHOD AND APPARATUS FOR PROGRAMMABLE CONTROLLER

摘要

PROBLEM TO BE SOLVED: To provide a sequence program, protected from reading etc. by a third party other than the author of the sequence program, a programmable controller and a recording medium having the sequence program stored therein, and a method and an apparatus for sequence program protection support.;SOLUTION: Sequence contents of the sequence program are rewritten by the use of the sequence program protection support apparatus which adds and deletes a NOOP code to/from the content of the sequence program. The NOOP code itself affects nothing on the operation processing of the programmable controller. The sequence program including the NOOP code is interpreted as illegal instruction description on the peripheral device side. The sequence program including the NOOP code, stored in the sequence program memory 4, is not displayed at all on a peripheral device 7. As a result, the sequence program becomes in the state of being protected, and the effluence of the sequence program can be prevented.;COPYRIGHT: (C)2011,JPO&INPIT