Mitsubishi Electronics FX3G Manuale Utente
243
FX
3S
/FX
3G
/FX
3GC
/FX
3U
/FX
3UC
Series
Programming Manual - Basic & Applied Instruction Edition
8 Program Flow – FNC 00 to FNC 09
8.10 FNC 09 – NEXT / End a FOR/NEXT Loop
1
Introdu
ction
2
Ov
ervi
ew
ew
3
Instruction
Li
st
4
D
evices
in Det
ai
l
5
Specifi
ed the
De
vice
&
C
onst
ant
ant
6
Bef
ore
ore
Pr
og
ra
mmi
ng
ng
7
Bas
ic
ic
Instruction
8
FN
C00-FN
C00-FN
C0
9
Program Fl
ow
9
FNC
10-FN
C19
Mov
e & Com
e & Com
pare
10
FNC
20-FNC
29
Arith. & Lo
gi
c
Operati
on
Errors
1. Watchdog timer error
When FOR-NEXT loop is repeated many times, the operation cycle (D8010) is too long, and a watchdog timer error
may occur. In such a case, change the watchdog timer time or reset the watchdog timer.
may occur. In such a case, change the watchdog timer time or reset the watchdog timer.
→ For details on changing the watchdog timer time, refer to Subsection 37.2.2.
→ For resetting the watchdog timer, refer to WDT (FNC 07) instruction.
2. Examples of wrong programs
The following programs are regarded as errors.
Program example
1. Program with three FOR-NEXT loops
When NEXT instruction does not exist
When NEXT instruction is located before FOR
instruction
instruction
When number of FOR instructions is not
equivalent to the number of NEXT instructions
equivalent to the number of NEXT instructions
← Not programmed
When NEXT instruction is located after FEND or
END instruction
END instruction
END
← Not programmed
FNC 09
NEXT
FNC 09
NEXT
FNC 09
NEXT
FNC 09
NEXT
FNC 09
NEXT
FNC 09
NEXT
FNC 08
FOR
FNC 08
FOR
FNC 08
FOR
FNC 06
FEND
FNC 08
FOR
FNC 08
FOR
The loop [3] is repeated 4 times.
When the data value (current value) of D0Z
(D4 when Z is "4") is "6", the loop [2] is
repeated 6 times.
(D4 when Z is "4") is "6", the loop [2] is
repeated 6 times.
When X010 is OFF
When K1X000 is "7", the loop [1] is repeated
7 times.
7 times.
When X010 is ON
The program execution jumps to the pointer P22,
and the loop [1] is skipped.
and the loop [1] is skipped.
Number of times of repeating the loops [1],
[2] and [3]
[2] and [3]
X010 = ON
X010 = OFF
7
× 6 × 4 =168 times
6
× 4 = 24 times
4 times
[1]
[2]
[3]
[2]
[3]
0 time
24 times
4 times
X010
P 22
[1]
[2]
[3]
FNC 09
NEXT
FNC 08
FOR
K 4
FNC 08
FOR
D 0Z
FNC 00
CJ
P 22
FNC 08
FOR
K1X000
FNC 09
NEXT
FNC 09
NEXT
7
times
times
6
times
times
4
times
times