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44 lines
1.5 KiB
Markdown
44 lines
1.5 KiB
Markdown
The [_LIMIT](_LIMIT) statement sets the loop repeat rate of a program to so many per second, relinquishing spare CPU cycles to other applications.
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## Syntax
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> [_LIMIT](_LIMIT) framesPerSecond!
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* The framesPerSecond! [SINGLE](SINGLE) parameter value adjusts the loops per second of a program loop. **Do not use negative values.**
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* The loop code is executed before the loop is delayed. Loop cycles below once per second may delay program [_EXIT](_EXIT)s.
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* _LIMIT measures its interval from the previous time that it was called and minor adjustments are automatically made to ensure that the number of times a loop is repeated is correct overall.
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* Loop cycle rates of 1000 or less can **significantly reduce CPU usage** in programs.
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* Do not use it to limit a loop to **less than once every 60 seconds**(.0167) or an [ERROR Codes](ERROR-Codes) will occur.
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* Do not use _LIMIT as a timing delay outside of loops. Use [_DELAY](_DELAY) instead.
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* Use _LIMIT to slow down old QBasic program loops that run too fast and use too much CPU.
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## Example(s)
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Limits loop execution to 30 frames per second and limits the program's CPU usage.
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```vb
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PRINT "To Quit press ESC key!"
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DO
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_LIMIT 30
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PRINT CHR$(26);
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IF INKEY$ = CHR$(27) THEN EXIT DO
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LOOP
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```
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```text
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To Quit press ESC key!
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→→→→→→→→→→→→→→→→→→→→
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```
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> *Note:* In the above example, _LIMIT has to be within the loop.
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## See Also
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* [_DELAY](_DELAY)
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* [TIMER](TIMER), [ON TIMER(n)](ON-TIMER(n))
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* [SLEEP](SLEEP)
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