| 摘要 |
PROBLEM TO BE SOLVED: To guarantee effectiveness of data of a common variable when updating a control program during operation of a PLC.SOLUTION: A switching instruction unit 73 of a development support device 20 transmits a switching instruction only to a write side PLC 10 relating to any of common variables, and the write side PLC transmits the switching instruction to a read side PLC 10 by a switching control unit 82 after completion of execution of a new machine language object of the write side PLC. Accordingly, after the execution of the new machine language object by the write side PLC 10, the read side PLC 10 is controlled to execute a new machine language object of the read side PLC 10. |
