Mitsubishi Electric MELSEC-L LD75D, User Manual

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CHAPTER 10 HIGH-LEVEL POSITIONING CONTROL
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10.3.8
Restrictions when using the NEXT start
The "NEXT start" is a instruction indicating the end of the repetitions when executing repeated start (FOR loop) (

Page 467, Section 10.3.6) and repeated start (FOR condition) (

Page 468, Section 10.3.7).
The following shows the restrictions when setting "6: NEXT start" in the " block start data".
• 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".
• 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.)
• 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.
When nest construction is not configured When nest construction is configured
A warning occurs when "FOR" of 4th point is executed.
Then, destination of jump by "NEXT" of 7th point is changed to 4th point and
"NEXT" of 9th point is processed as "Normal execution".
Da.13
FOR
NEXT
FOR
NEXT
Start block data
1st point
2nd point
3rd point
4th point
5th point
6th point
7th point
8th point
9th point
Special start command
Normal start
Normal start
Normal start
Normal start
Normal start
Da.13
FOR
FOR
NEXT
NEXT
Start block data
1st point
2nd point
3rd point
4th point
5th point
6th point
7th point
8th point
9th point
Special start command
Normal start
Normal start
Normal start
Normal start
Normal start