MITSUBISHI ELECTRIC Mitsubishi Programmable Logic Controller QD75D - Manual (Page 273)

7 - 9
MELSEC-Q
7 MEMORY CONFIGURATION AND DATA PROCESS
(5) Flash ROM write ( )
The following transmission process is carried 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 transmitted to the flash ROM.
The writing to the flash ROM may also be carried out using a dedicated
instruction "PFWRT". (Refer to Chapter 14 "Dedicated instructions" for details.)
(6) Flash ROM request (writing) ( )
The following transmission processes are carried out 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 transmitted to the flash ROM.
Note) This transmission process is the same as (5) above.
IMPORTANT
(1) Do not turn the power OFF or reset the PLC CPU while 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 memory before writing to the flash ROM is
completed.
(3) The number of writes to the flash ROM with the PLC program is 25 max. while
the power is turned ON.
Writing to the flash ROM beyond 25 times will cause an error (error code: 805).
Refer to Section 15.2 "List of errors" for details.