6
FUNCTIONS
6.2 Constant scan
6
- 7
1
O
verv
iew
2
Per
fo
rma
nce
S
p
ecifica
tio
n
3
S
equ
en
ce P
ro
g
ra
m
Co
nfig
ura
tio
n a
nd
E
xecut
io
n Co
nd
iti
o
ns
4
I/O N
unb
er
Assig
n
m
e
nt
5
Me
mor
ie
s a
nd
File
s
Ha
nd
led
by CP
U Mo
du
le
6
Func
tions
7
Co
mmu
nic
a
tion
us
in
g
bu
ilt
-i
n E
th
e
rne
t po
rt
s o
f
CP
U mod
u
le
8
Co
mm
un
icatio
n
w
ith
Int
e
lli
ge
nt
Fun
ction
Mo
du
le
(a) Setting time condition
As the constant scan time, set a value that satisfies the following relational
expression.
If the sequence program scan time is longer than the constant scan setting time,
the CPU module detects PRG. TIME OVER (error code: 5010).
In this case, the constant scan setting is ignored and the sequence program is
executed based on its scan time.
If the sequence program scan time is longer than the WDT setting time, the CPU
module detects a WDT error.
In this case, the program execution is stopped.
(WDT Set Time) > (Constant Scan Set Time)
> (Sequence Program maximum Scan Time)
Figure 6.3 Operation when the Scan Time is longer than the Constant Scan
0
1
2
3
4
1
2
3
4
0
0
1
END 0
END
2
3
4
1
2
3
4
0
END
0
END
3.5ms
0.5ms
4ms
4ms
3.5ms
3.4ms
0.6ms
4ms
5.3ms
5
ms
0.5ms
Scan where the constant scan is not normal
Constant scan setting
Constant
scan
Sequence
program
(Setting time: 4ms)
Содержание Q00CPU
Страница 1: ......
Страница 2: ......
Страница 972: ...Index 6 Memo ...
Страница 975: ......
Страница 976: ......