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Re: [gpsd-dev] PPS and doubles

From: Hal Murray
Subject: Re: [gpsd-dev] PPS and doubles
Date: Sun, 01 Feb 2015 15:06:16 -0800

address@hidden said:
> Delay is 53 bits of precision.
> tv_sec is 32, soon to be 33 bits of precision
> tv_nsec = 20 bits of precision

> So (tv_sec + tv_nsec / 1e9) is 63 bits of precision.
> 63 bits of precision does not fit in 53 bits of double! 

Took me a while to understand that.
33+20 is 53, not 63.
Looks like a typo here:
  tv_nsec = 20 bits of precision
Microseconds would be 20 bits.  Nanoseconds are 30 bits.

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