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Re: [gpsd-dev] A detail in your ntpoffset script
From: |
Eric S. Raymond |
Subject: |
Re: [gpsd-dev] A detail in your ntpoffset script |
Date: |
Wed, 23 Oct 2013 16:17:07 -0400 |
User-agent: |
Mutt/1.5.21 (2010-09-15) |
Gary E. Miller <address@hidden>:
> Acually. It is much simpler. There are USB 1.1 1024 time slots. That
> works about to a time slot every 1 mSec. Each device is always polled
> in the same time slot. The time slots are derived from the system
> clock. So once the system clock is stable the sample instant is euqally
> stable. Once it settles I get an observed stability of one part in
> about 1,000.
Aha. So *that's* why USB time latency is so freaking steady. Good to
know. Maybe should go in the HOWTO.
--
<a href="http://www.catb.org/~esr/">Eric S. Raymond</a>
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- Re: [gpsd-dev] A detail in your ntpoffset script, (continued)
- Re: [gpsd-dev] A detail in your ntpoffset script, Gary E. Miller, 2013/10/22
- Re: [gpsd-dev] A detail in your ntpoffset script, Eric S. Raymond, 2013/10/22
- Re: [gpsd-dev] A detail in your ntpoffset script, Hal Murray, 2013/10/23
- Re: [gpsd-dev] A detail in your ntpoffset script, Gary E. Miller, 2013/10/23
- Re: [gpsd-dev] A detail in your ntpoffset script, Dave Platt, 2013/10/23
- Re: [gpsd-dev] A detail in your ntpoffset script, Gary E. Miller, 2013/10/23
- Re: [gpsd-dev] A detail in your ntpoffset script,
Eric S. Raymond <=
- Re: [gpsd-dev] A detail in your ntpoffset script, Harlan Stenn, 2013/10/23
- Re: [gpsd-dev] A detail in your ntpoffset script, Harlan Stenn, 2013/10/23
- Re: [gpsd-dev] A detail in your ntpoffset script, Gary E. Miller, 2013/10/23
- Re: [gpsd-dev] A detail in your ntpoffset script, Sanjeev Gupta, 2013/10/24
Re: [gpsd-dev] A detail in your ntpoffset script, Andy Walls, 2013/10/22