Flash Rom Write Function; Control Details - Mitsubishi Electric MELSEC Q Series User Manual

10 FUNCTION DETAILS

10.22 Flash ROM Write Function

10.22.1 Control details

When the buffer memory data of QD74MH are rewritten from the PLC CPU, the
changed data are not saved if the system's power supply is turned OFF.
This function is used to backup by writing the changed data to the flash ROM. The
data that was backed up is written to the buffer memory when the system's power
supply is turned ON next.
The flash ROM write is executed by setting "1" in "
"0" is automatically set in "flash ROM write request" by QD74MH after writing.
Important
Do not turn the system's power ON/OFF or resetting PLC CPU in writing to the
flash ROM. The flash ROM data may be corrupted.
The data that can be written to the flash ROM by flash ROM write are shown below.
• Basic parameters
• OPR parameters
• Manual control parameters
• System parameters
• Positioning data
• Servo parameters
POINT
The absolute position information is automatically backed up in the absolute
position system. It is not necessary to back up them by the flash ROM write
function.
(1) Cautions
(a) Execute the flash ROM write when the positioning control do not execute
(PLC READY signal [Y0] OFF).
(b) A writing to the flash ROM is up to 100,000 times. If writing exceeds
100,000 times, the writing may be become impossible, and an "error code
1901" will occur.
(c) The total number of the flash ROM write and parameter initialization with
the sequence program after the error reset, system's power supply ON or
PLC CPU reset is limiter to up to 25. Writing of the 26th will cause an "error
code 1902". Execute the error reset, system's power cycle or PLC CPU
reset at error occurrence.
(d) The flash ROM write can be executed, after the system's power supply ON
and the PLC READY signal [Y0] ON. If the flash ROM write is executed
without turning ON the PLC READY signal [Y0] after the system's power
supply ON, a "warning code 10001" will occur and the flash ROM write
cannot be executed.
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MELSEC-Q
Flash ROM write request".
Cd.100