,
,.A
C..
L.
r-
r-
I
c-
c
c-
c
i
..
P
LI
P
P-
b-
.
c
c
4.
A2CCPU
/MELSEC-A
4.2.1
Constant
rcrn
Because the processing time of each individual instruction in
a
sequence program differs depending
on
whether or not the
instruction is executed, the scan time differs accordingly for each
scan.
The constant scan function sets such varying scan times to
a
fixed
value regardless
of
the sequence program processing time.
Scan timeconstant scan function not used
I
Sequence program
END processing
0
END
0
END
0
Scan time-scan time fixed to 7Omsec
1
/
/-END Drocesrina
Sequence program
Fig.
4.11
Constant
SCM
Function
(1) Setting range
(a) Constant scan time can
be
set
in
the range of 10 msec to
200
msec.
Enter the required constant scan time to special register
09020
in
units of 10 msec (setting value between
10
and
2000).
If
09020
is
set outside the range of lmsec to
2000
msec,
the constant scan time will
be
set
as
indicated
below.
(kWngforD8020
CoMt.nt
8un
Tima
-32768 to
0
Not
set
1
to 200
10
msec
to
2OOO
msec
201
to 32767
2000 msec