13 - 6 
MELSEC-Q
13   COMMON FUNCTIONS 
 
[4]   Execution data backup method 
(1) Execution data backup (writing to the flash ROM) is carried out using the 
dedicated instruction "PFWRT". (Refer to CHAPTER 14 "DEDICATED 
INSTRUCTIONS" for details.) 
 
(2) Refer to Section 7.2 "Data transmission process" for the data transmission 
processing at the backup of the execution data. 
 
(3) Execution data backup can also be carried out by the writing of the data 
shown in the table below to the QD75 buffer memory using the TO instruction 
/intelligent function device. 
The writing to the flash ROM is executed at the time point the data is written 
to the QD75 buffer memory. 
 
Buffer memory address
Setting item 
Setting 
value 
Setting details 
Axis 
1 
Axis 
2 
Axis 
3 
Axis 
4 
Cd.1
 
Flash ROM write 
request 
1  Set "1" (flash ROM write request).  1900 
 
   Refer to Section 5.7 "List of control data" for details on the setting details. 
 
When the writing to the flash ROM is complete, "0" will be set in "
Cd.1
 Flash 
ROM write request" by the QD75 automatically.