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99 lines
2.3 KiB
HTML
99 lines
2.3 KiB
HTML
<HTML>
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<HEAD>
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<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
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<META NAME="GENERATOR" CONTENT="Mozilla/4.01 [en] (Win95; I) [Netscape]">
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<TITLE>KSI/Odetics TPRO/S IRIG Interface
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</TITLE>
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</HEAD>
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<BODY>
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<H3>
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KSI/Odetics TPRO/S IRIG Interface</H3>
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<HR>
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<H4>
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Synopsis</H4>
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Address: 127.127.12.<I>u</I>
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<BR>Reference ID: <TT>IRIG</TT>
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<BR>Driver ID: <TT>IRIG_TPRO</TT>
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<BR>TPRO Device: <TT>/dev/tpro<I>u</I></TT>
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<BR>Requires: KSI/Odetics device driver, <TT>/usr/include/sys/tpro.h</TT> header file
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<H4>
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Description</H4>
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This driver supports the KSI/Odetics TPRO and TPRO-SAT IRIG-B Decoder,
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which is a module connected directly to the SBus of a Sun workstation.
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The module works with the IRIG-B signal generated by several radio clocks,
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including those made by Arbiter, Austron, Odetics, Spectracom and TrueTime,
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among others, although it is generally an add- on option. In the case of
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the TPRO-SAT, the module is an integral part of a GPS receiver, which serves
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as the primary timing source.
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<P>Using the TPRO interface as a NTP reference clock provides precision
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time only to ntpd and its clients. With suitable kernel modifications,
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it is possible to use the TPRO as the CPU system clock, avoiding errors
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introduced by the CPU clock oscillator wander. See the <A HREF="kern.htm">A
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Kernel Model for Precision Timekeeping </A>page for further details.
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<H4>
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Fudge Factors</H4>
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<DL>
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<DT>
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<TT>time1 <I>time</I></TT></DT>
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<DD>
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Specifies the time offset calibration factor, in seconds and fraction,
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with default 0.0.</DD>
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<DT>
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<TT>time2 <I>time</I></TT></DT>
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<DD>
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Not used by this driver.</DD>
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<DT>
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<TT>stratum <I>number</I></TT></DT>
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<DD>
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Specifies the driver stratum, in decimal from 0 to 15, with default 0.</DD>
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<DT>
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<TT>refid <I>string</I></TT></DT>
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<DD>
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Specifies the driver reference identifier, an ASCII string from one to
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four characters, with default <TT>IRIG</TT>.</DD>
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<DT>
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<TT>flag1 0 | 1</TT></DT>
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<DD>
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Not used by this driver.</DD>
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<DT>
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<TT>flag2 0 | 1</TT></DT>
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<DD>
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Not used by this driver.</DD>
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<DT>
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<TT>flag3 0 | 1</TT></DT>
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<DD>
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Not used by this driver.</DD>
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<DT>
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<TT>flag4 0 | 1</TT></DT>
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<DD>
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Not used by this driver.</DD>
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</DL>
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Additional Information
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<P><A HREF="refclock.htm">Reference Clock Drivers</A>
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<HR>
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<ADDRESS>
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David L. Mills (mills@udel.edu)</ADDRESS>
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</BODY>
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</HTML>
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