Considerations For Mode Switching - Mitsubishi Electric MELSEC iQ-R Series User Manual

19.2

Considerations for Mode Switching

Modification of buffer memory stored value
Determine the following items between the target device and the CPU module to prevent mode switching during data
communications.
• How to perform mode switching - from the target device or by program
• Timing for each mode switching pattern (Page 378 Operation for mode switching)
• Interlocking of all connected devices for mode switching
Method to configure interlock when informing all of the connected stations the mode switching execution
Method and message structure when informing all of the connected stations the mode switching completion
Device number and meaning of the value when a CPU module word device is used
Mode switching from target device
• Once the mode has been switched to a mode other than MC protocol (Formats 1 to 5), it cannot be changed from the target
device.
In this case, switch the mode by program.
• Mode switching from the target device can be performed to only C24 connected to a target device (including connected
stations by multidrop connection).
It is not available for C24s on the other stations via network system. ( MELSEC Communication Protocol Reference
Manual)
It is recommended to perform mode switching by program.
Data communications after mode switching
While the mode switching is being executed, data communications between C24 and the target device cannot be performed,
including the processing time to store the setting value to the special applications area on the buffer memory.
Mode switching
processing
Mode switching in progress signal
X6/XD
Mode switching related to interlink operation
Do not switch the mode when the two interfaces of C24 are in the interlink operation. Also, do not switch the mode for the
interlink operation.
19 SWITCHING THE MODE AFTER STARTING
19.2 Considerations for Mode Switching
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