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Old 12-12-2010, 07:21 PM   #35 (permalink)
bobski
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Quote:
Originally Posted by saand View Post
you will have a big problem getting accurate timing unless you sink the clock to some external (more accurate) timing device than what the processor runs on.
That's what led me to RTC chips in the first place. I made a simple stopwatch-timer program based on the millis() function and let it run over night along side a timex wristwatch. After about 10 hours, it was off by a minute and change. That's something like 0.2% error, which is fine for tracking injector pulses and such. On the other hand, losing an hour and a half every month isn't up to snuff for time keeping.
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