| 摘要 |
PURPOSE:To limit the change of a control parameter only to a specific person by storing a collation code limiting the specific person to a memory and providing this memory to a process controller for control of a process control subject. CONSTITUTION:A ROM1 for applied software which stores the control information is removed from a program loader and then attached to a process controller. A person who wants the change of a control parameter supplies a collation code through a keyboard 21. A CPU20 stores an input code in a collation area 28a of a RAM28. When a request is given for change, the CPU20 reads out the collation code stored in a RAM28 and the collation code of the ROM1 and compares them with each other. If coincidence is obtained between both collation codes, the CPU20 permits the change of the control parameter. When no coincidence is obtained, the CPU20 inhibits the change of the control parameter.
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