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MELSEC-Q
7 MEMORY CONFIGURATION AND DATA PROCESS
(5) Flash ROM write ( )
The following transmission process is carr ied out by setting "1" in " Cd.1 Flash
ROM write request" (buffer memory [1900]).
1) The "parameters", "positioning data (No. 1 to 600)" and "block start data (No.
7000 to 7004)" in the buffer memory area are transmitte d to th e fl a sh R OM .
The writing to the flash ROM may also be carried out using a de di ca ted
instruction "PFWRT". (Refer to Chapter 14 "Dedicated i nstructions" for details.)
(6) Flash ROM request (writing) ( )
The following transmission processes are carried o ut with the [flash ROM
request] (write) from the peripheral device.
1) The "parameters", "positioning data (No. 1 to 600)" and "block start data (No.
7000 to 7004)" in the buffer memory area are transmitte d to th e fl a sh R OM .
Note) This transmission process is the same as (5) above.
IMPORTANT
(1) Do not turn the power OFF or reset the PLC CPU whil e writing to the flash
ROM. If the power is turned OFF or the PLC CPU is reset to forcibly end the
process, the data backed up in the flash ROM will be lost.
(2) Do not write the data to the buffer memor y before writing to the flash ROM is
completed.
(3) The number of writes to the flash ROM with th e PLC program is 25 max. while
the power is turned ON.
Writing to the flash ROM beyond 25 times will cause an error (er ro r code : 805 ).
Refer to Section 15.2 "List of errors" for details.