Mitsubishi QCPU (Q Mode), Руководство пользователя

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MELSEC-Q
10 DEVICES
(c) The timer response accuracy from when reading input (X), until when
outputing it is + (2-scan time + timer time limit setting).
Precautions for using timers
The following are a few precautions regarding timer use:
(a) A given timer cannot be designated (by OUT T ) more than once in a
single scan.
This designation results in measurement, since the timer current value is
updated at execution of each OUT T instruction.
Sequence
program
END
END
OUT
T OUT
T OUT
T OUT
T
Current value is updated.
1 Scan
OUT
T
(b) When a timer (for example. T1) coil is ON, the OUT T1 instruction cannot be
skipped using a CJ instruction, and so forth.
If the OUT T instruction is skipped, the timer current value will not be
updated.
(c) Timers cannot be used in interrupt programs and fixed scan execution
programs.
(d) If the timer set value is "0", the contact turnes ON when the OUT T
instruction is executed.
(e) If the set value changes to a value which is higher than the current value
following a timer "time-out", the "time-out" status will remain in effect, and
timer operation will not be performed.
(f) If a timer is used at a low speed execution type program, the current value
will be added to the low speed scan time when the OUT T instruction is
executed.
See Section 4.3.2 for details on the low speed scan time.
(g) If two timers are used, the ON/OFF ladders should be created as shown
below.
T0
M0
T1
T0
K10
T0
T1
K10
1 second measurement
following T0 ON
1 second measurement
when T1 ON
ON/OFF repeated every
1 second