Mitsubishi Q Series User Manual page 48

3 SPECIFICATIONS
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(2) Writing data to FeRAM
(a) When writing data to FeRAM, turn on the FeRAM backup command (Yn8).
• The FeRAM write completion flag (Xn8) turns on at completion of data
write to FeRAM.
• After turning on Yn8, it takes more than ten seconds until Xn8 is on.
• The FeRAM write failure flag (XnA) turns on if write of data to FeRAM is
not completed normally.
(b) Make changes to buffer memory when the FeRAM write completion flag
(Xn8) is off.
Programmable
controller CPU
1) Yn8 : ON
(Write command)
3) Xn8 : ON
(completed)
(3) Reading data from FeRAM
FeRAM data read occurs under either of the following conditions.
• When the programmable controller CPU is powered on or reset.
• When the FeRAM's PID constant read command (Buffer memory address: 62,
94) turns on. Note that the read data are only the PID constants and loop
disconnection detection judgment time of the corresponding channel.
Q62HLC
OS
2) Write
Buffer
memory
data
Read
At power-on
or reset
MELSEC-Q
FeRAM
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