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Thread: Accurate Timestamp On T4.0

  1. #1
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    Accurate Timestamp On T4.0

    I'm testing out TimeLib.h for getting an accurate (us) timestamp on sensor readings. I'm able to run the TimeTeensy3 example just fine, but not seeing how I use TimeLib to get a us-level timestamp. I suppose I could use micro() somehow and try to line that up with every one-second interval, but seems like there's probably an easier way.

    P.S. I searched the forum and didn't see this explicitly. Apologize if I missed this if it's already been addressed.

  2. #2
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    Update:
    Got a 1sec RTC interrupt timer working (derived from code posted in the forum). So I just need to add my own uSec sub-timer. But am still surprised there's not a lib out there that allows us to easily (precisely) timestamp an incoming sensor reading. If someone has seen one, I'd appreciate a link!

  3. #3
    Senior Member+ manitou's Avatar
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    although most of the T4 RTC example sketches just return seconds. The T4 RTC registers (2 32-bit registers) actually count 32768 ticks, so you could get sub-second values at a precision of 1/32768. of course if you don't need time-of-day values, micros() will give you microsecond resolution timestamps.

  4. #4
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    manitou, thanks. Yes, I'm aware of micros(), but need it relative to time of day. I searched for RTC registers on the forum and found this link:

    https://forum.pjrc.com/threads/53372...=RTC+registers

    Thinking it has some really good ideas, but will take me awhile to digest!

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