Interrupts

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does use of interrupts affect internal clock of arduino?   i using interrupt signal generated as  hole in rotating
disc passes between ir led , photo-diode. time when rotation starts and  when rotation ends , subtract 2 give measure of running time.  find that  on 1 minute of running time, consistent 54 seconds indicated.
when measure time without using interrupts accurate 60 seconds indicated 1 minute. idea what's going on?

quote from: glynne on mar 27, 2014, 11:47 am

does use of interrupts affect internal clock of arduino?


it might, rather depends on how bad code looks.  unless post examination (using "code" tags - [ # ] icon), no-one here can tell you.

this excellent example of why should not try use interrupts not needed or appropriate, , description of optical interrupter on shaft classic example interrupt inappropriate.   :d


Arduino Forum > Using Arduino > Project Guidance > Interrupts


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