Appendix 5 Special Register List - Mitsubishi Electric MELSEC iQ-R Series User Manual

Appendix 5
The following table shows how to read the list of special registers (SD).
Item
No.
Name
Content
Details
Set by (when to set)
Do not change the special registers which are to be set by the system by performing operations such as
program execution and device test. Doing so may result in system down or disconnection of communication.
APPX
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Appendix 5 Special Register List

Special Register List
Description
The number of the special register is indicated.
The name of the special register is indicated.
The content of the special register is indicated.
The details of the special register is indicated.
The timing to set each device by system and/or user is indicated.
(Set by)
• S: Set by a system
• U: Set by a user (by a program, engineering tool, GOT, or test function from an external device).
(When to set)
• System: Set when a fixed cycle or the status is changed in the system.
• Initial: Set only when any of the following operations is performed: turning the power OFF and ON, resetting the
hardware, or resetting the bus. (It is not required for a Windows restart.)
• Status change: Set only when the status is changed.
• Error occurrence: Set when an error occurs.
• Key switch change: Set when the key switch is changed.