Yaskawa MP900 Series Motion Programming Manual - Manual (Page 111)

3.1 High-Level Control Commands
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3.1.10 Repeat Commands: WHILE...WEND
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Overview
The repeat commands (WHILE...WEND) repeatedly execute a designated range of blocks for
as long as the conditional expression is satisfied.
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Description
The repeat commands (WHILE...WEND) are designated as follows:
WHILE (conditional_expression);
⋅⋅⋅ ;
⋅⋅⋅ ; (process_1)
⋅⋅⋅ ;
WEND ; ← End of REPEAT
With these commands, the blocks from WHILE to WEND are repeatedly executed as long as
the conditional expression is satisfied. When the conditional expression is no longer satisfied,
program execution will jump to the next block after WEND.
Conditional
expression
Not satisfied
Satisfied
Process
1. Nesting of the repeat commands (WHILE...WEND) is restricted to a maximum of eight levels.
2. If the repeated program section is created using only commands for which processing is completed in one
scan, an infinite loop will be created and a watchdog timer error (system error) will be generated. When
using a command for which processing is executed in one scan, be sure to enter the SCAN WAIT (EOX)
command.
3. The commands for which processing is not completed in one scan are as follows:
MOV, MOS, MCW/MCC, ZRN, SKP, MVT, EXM, ACC, SCC, PFN, VEL, INP, TIM, and IOW
4. Processing of all commands other than those listed above is completed in one scan.
ABS, INC, IFP, PLN, IAC, IDC, FMX, POS, PLD, MSEE, END, RET, IF, WHILE, PFORK, SFORK,
and all sequence commands
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IMPORTANT