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fred
post Dec 23 2007, 01:36 PM
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I'm running at 4000000 clock and using a delay_us( 10 );

Boostc gives me the warning
Caution: Delay inaccurrate: 'delay_us', Delay overhead:0.01ms, Unit delay:0.001ms

How do I interpret the overhead and unit delay....?

delay_us( 1 ) -> 12us
delay_us(12) -> 23us
delay_us(13) -> 24us
or
delay_us(1) -> 12us
delay_us(12) -> 12us
delay_us(13) -> 13us
or
???
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fred
post Dec 23 2007, 10:11 PM
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Roger!!!

thanks

uhhh, so delay_us(0) results in 0.01ms + (0 * 0.001ms) = 10us..!? smile.gif

This post has been edited by fred: Dec 23 2007, 10:13 PM
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Dave
post Dec 24 2007, 10:18 AM
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Fred,
QUOTE (fred @ Dec 23 2007, 10:11 PM) *
Roger!!!

thanks

uhhh, so delay_us(0) results in 0.01ms + (0 * 0.001ms) = 10us..!? smile.gif
No, minimum delay value for delay us is 1.

delay_us(0) results in 0.01ms + (255 * 0.001ms) = 265us smile.gif

Regards
Dave
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Posts in this topic
- fred   Delay Overhead   Dec 23 2007, 01:36 PM
- - Dave   fred, QUOTE (fred @ Dec 23 2007, 01:36 PM...   Dec 23 2007, 03:52 PM
- - fred   Roger!!! thanks uhhh, so delay_us(0)...   Dec 23 2007, 10:11 PM
- - Dave   Fred, QUOTE (fred @ Dec 23 2007, 10:11 PM...   Dec 24 2007, 10:18 AM

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