Mitsubishi Electric MELSEC iQ-R Series User Manual page 46

Section 4 I/O SIGNALS TO CPU MODULE
(c) Synchronizing method
Please note as below in order to acquire measured data by synchronizing with this module.
(i) The program is configured to set the scan time of ladder program will be within below range.
The scan time should be shorter than ON time and OFF time in order to detect "OFF → ON" of the
signal (Xn8).
Period of measured data
acquisition clock
10ms
20ms to 10000ms
(ii) Acquire data by detecting "OFF → ON" of the signal (Xn8).
Measured data is updated immediately before the signal (Xn8) is ON. Since the last value and latest
value are mixed while updating, it is able to acquire measured data at a timing as below.
Scan time of ladder program
Less than 2ms
2/5 of the period of measured data acquisition clock
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