78 lines
2.4 KiB
HTML
78 lines
2.4 KiB
HTML
<!-- $NetBSD: driver12.html,v 1.1 1998/12/30 20:20:34 mcr Exp $ -->
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<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML Strict//EN">
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<html><head><title>
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KSI/Odetics TPRO/S IRIG Interface
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</title></head><body><h3>
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KSI/Odetics TPRO/S IRIG Interface
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</h3><hr>
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<p><h4>Synopsis</h4>
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<p>Address: 127.127.12.<var>u</var>
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<br>Reference ID: IRIG
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<br>Driver ID: IRIG-TPRO
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<br>TPRO Device: <code>/dev/tpro<var>u</var></code>
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<br>Requires: KSI/Odetics device driver,
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<code>/usr/include/sys/tpro.h</code> header file
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<p><h4>Description</h4>
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<p>This driver supports the KSI/Odetics TPRO and TPRO-SAT IRIG-B
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Decoder, which is a module connected directly to the SBus of a Sun
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workstation. The module works with the IRIG-B signal generated by
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several radio clocks, including those made by Arbiter, Austron, Odetics,
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Spectracom and TrueTime, among others, although it is generally an add-
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on option. In the case of the TPRO-SAT, the module is an integral part
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of a GPS receiver, which serves 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 xntpd 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 =
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"kern.html"> A Kernel Model for Precision Timekeeping </a> page for
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further details.
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<p><h4>Monitor Data</h4>
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<p>The driver writes each timecode as received to the
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<code>clockstats</code> file.
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<p><h4>Fudge Factors</h4>
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<dl>
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<dt><code>time1 <i>time</i></code>
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<dd>Specifies the time offset calibration factor, in seconds and
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fraction, with default 0.0. For a calibrated Sun IPC, the correct value
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is about .00037.
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<p><dt><code>time2 <i>time</i></code>
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<dd>Not used by this driver.
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<p><dt><code>stratum <i>number</i></code>
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<dd>Specifies the driver stratum, in decimal from 0 to 15, with default
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0.
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<p><dt><code>refid <i>string</i></code>
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<dd>Specifies the driver reference identifier, an ASCII string from one
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to four characters, with default <code>IRIG</code>.
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<p><dt><code>flag1 0 | 1</code>
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<dd>Not used by this driver.
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<p><dt><code>flag2 0 | 1</code>
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<dd>Not used by this driver.
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<p><dt><code>flag3 0 | 1</code>
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<dd>Not used by this driver.
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<p><dt><code>flag4 0 | 1</code>
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<dd>Not used by this driver.
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</dl>
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<p>Additional Information
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<p><a href="refclock.html"> Reference Clock Drivers</a>
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<hr><address>David L. Mills (mills@udel.edu)</address></body></html>
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