Mitsubishi Electric MELSEC iQ-R16MTCPU Programming Manual page 78

[Device writing precautions]
Do not write to the following devices from the Motion CPU. Writing will be ignored, or a malfunction will occur.
• Actual input devices, or I/O number that is not allocated to any module and is within range of the maximum
I/O number for the modules being used, from inputs (X).
• Actual output devices from outputs (Y) for which other CPU management performed.
• Other CPU buffer memory access devices (U3E\G, U3E\HG).
• Other CPU management module access devices (U\G).
• Devices updated at the module side from module access devices (U\G).
• Devices other than user set devices from special relays (SM), special registers (SD).
• Monitor signals from internal relay (M), data register (D), Motion register (#) dedicated positioning devices.
3 DEVICES
76
3.1 Device List