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From: Wolfgang Denk <wd@denx.de>
To: Jerry Van Baren <vanbaren_gerald@si.com>
Cc: linuxppc-embedded@lists.linuxppc.org
Subject: Re: Using realtime clock?
Date: Wed, 10 Jan 2001 17:22:58 +0100	[thread overview]
Message-ID: <200101101622.f0AGMw208453@denx.local.net> (raw)
In-Reply-To: Your message of "Wed, 10 Jan 2001 10:56:58 EST." <4.3.2.20010110104647.00baee80@falcon.si.com>


In message <4.3.2.20010110104647.00baee80@falcon.si.com> you wrote:
>
> The astronomy people, among others, are really fanatical about accurate
> time and have some very elaborate programs to synchronize clocks to the
> nanosecond (microsecond?) level.  These involve NTP daemons.  Note that
> the NTP daemons can synchronize to a radio clock that provides a
> 1/second tick: your simplest solution would probably be to set up your
> accurate RTC to do a 1/second interrupt and then tie it into a NTP
> daemon to keep your kernel clock accurate.

Seems a bit of overhead (especially for embedded systems with limited
resources) to add a NTP daemon just to make one part  of  the  kernel
timekeeping toal to the other...

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd@denx.de
"It's when they say 2 + 2 = 5 that I begin to argue."    - Eric Pepke

** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

  reply	other threads:[~2001-01-10 16:22 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-01-10  4:16 Using realtime clock? Jari Nguyen Trung Thanh
2001-01-10  9:30 ` Gabriel Paubert
2001-01-10 12:33   ` Jerry Van Baren
2001-01-10 13:22     ` Jari Nguyen Trung Thanh
2001-01-10 15:06     ` Wolfgang Denk
2001-01-10 15:56       ` Jerry Van Baren
2001-01-10 16:22         ` Wolfgang Denk [this message]
2001-01-10 16:51           ` Jerry Van Baren
2001-01-10 16:59             ` Bill Roman
2001-01-10 19:16             ` Gabriel Paubert
2001-01-10 19:05         ` Gabriel Paubert

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