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KSI/Odetics TPRO/S IRIG Interface
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KSI/Odetics TPRO/S IRIG Interface
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<p><h4>Synopsis</h4>

<p>Address: 127.127.12.<var>u</var>
<br>Reference ID: IRIG
<br>Driver ID: IRIG-TPRO
<br>TPRO Device: <code>/dev/tpro<var>u</var></code>
<br>Requires: KSI/Odetics device driver,
<code>/usr/include/sys/tpro.h</code> header file

<p><h4>Description</h4>

<p>This driver supports the KSI/Odetics TPRO and TPRO-SAT IRIG-B
Decoder, which is a module connected directly to the SBus of a Sun
workstation. The module works with the IRIG-B signal generated by
several radio clocks, including those made by Arbiter, Austron, Odetics,
Spectracom and TrueTime, among others, although it is generally an add-
on option. In the case of the TPRO-SAT, the module is an integral part
of a GPS receiver, which serves as the primary timing source.

<p>Using the TPRO interface as a NTP reference clock provides precision
time only to xntpd and its clients. With suitable kernel modifications,
it is possible to use the TPRO as the CPU system clock, avoiding errors
introduced by the CPU clock oscillator wander. See the <a href =
"kern.html"> A Kernel Model for Precision Timekeeping </a> page for
further details.

<p><h4>Monitor Data</h4>

<p>The driver writes each timecode as received to the
<code>clockstats</code> file.

<p><h4>Fudge Factors</h4>

<dl>

<dt><code>time1 <i>time</i></code>
<dd>Specifies the time offset calibration factor, in seconds and
fraction, with default 0.0. For a calibrated Sun IPC, the correct value
is about .00037.

<p><dt><code>time2 <i>time</i></code>
<dd>Not used by this driver.

<p><dt><code>stratum <i>number</i></code>
<dd>Specifies the driver stratum, in decimal from 0 to 15, with default
0.

<p><dt><code>refid <i>string</i></code>
<dd>Specifies the driver reference identifier, an ASCII string from one
to four characters, with default <code>IRIG</code>.

<p><dt><code>flag1 0 | 1</code>
<dd>Not used by this driver.

<p><dt><code>flag2 0 | 1</code>
<dd>Not used by this driver.

<p><dt><code>flag3 0 | 1</code>
<dd>Not used by this driver.
<p><dt><code>flag4 0 | 1</code>
<dd>Not used by this driver.

</dl>

<p>Additional Information

<p><a href="refclock.html"> Reference Clock Drivers</a>

<hr><address>David L. Mills (mills@udel.edu)</address></body></html>
