Mitsubishi Electric MELSEC Q Series User Manual page 81

6 DATA USED FOR POSITIONING CONTROL
(2) Reading/writing data from buffer memory
Read and write the data from the buffer memory in the following method.
(a) Reading
1) Sequence program
• 1 word .......... Use FROM instruction or intelligent function device.
• 2 word .......... Use DFRO instruction or intelligent function device.
(b) Writing
1) Sequence program
• 1 word .......... Use TO instruction or intelligent function device.
• 2 word .......... Use DTO instruction or intelligent function device.
(3) Saving data
Data of the buffer memory cannot be backed up, and the all data are transmitted
from FLASH ROM at the system power supply ON or reset of the PLC CPU.
Therefore, back up the data required for positioning using the flash ROM write
function.
Refer to Section 10.22 for the flash ROM write function.
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MELSEC-Q