10 HIGH-LEVEL POSITIONING CONTROL
10.3.8 Restrictions when using the NEXT start
The "NEXT start" is a instruction indicating the end of the repetitions when executing
Section 10.3.6 "Repeated start (FOR loop)" and Section 10.3.7 "Repeated start (FOR
condition)".
The following shows the restrictions when setting "6: NEXT start" in the " block start
data".
(1) The processing when "6: NEXT start" is set before execution of "4: FOR loop" or
"5: FOR condition" is the same as that for a "0: block start".
(2) Repeated processing will not be carried out if there is no "6: NEXT start"
instruction after the "4: FOR loop" or "5: FOR condition" instruction. (Note that an
"error" will not occur.)
(3) Nesting is not possible between "4: FOR loop" and "6: NEXT start", or between
"5: FOR condition" and "6: NEXT start". A warning "FOR to NEXT nest
construction (warning code: 506)" will occur if nesting is attempted.
Block start data
Special start instruction
1st point
2nd point
3rd point
4th point
5th point
6th point
7th point
8th point
9th point
•
•
Da.13
Block start
FOR
Block start
FOR
Block start
Block start
NEXT
Block start
NEXT
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MELSEC-Q
The JUMP destination of the
NEXT designated with points
7 and 9 is the FOR of point 4.
A warning will occur if the NEXT
designated with point 9 is
executed.