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<h3>Magnavox MX4200 GPS Receiver</h3>
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<h4>Synopsis</h4>
Address: 127.127.9.<i>u</i><br>
Reference ID: <tt>GPS</tt><br>
Driver ID: <tt>GPS_MX4200</tt><br>
Serial Port: <tt>/dev/gps<i>u</i></tt>; 4800 baud, 8-bits, no parity<br>
Features: <tt>ppsclock</tt> (required)
<h4>Description</h4>
<p>This driver supports the Magnavox MX4200 Navigation Receiver adapted to precision timing applications. It requires the <tt>ppsclock</tt> line discipline or streams module described in the <a href="../ldisc.html">Line Disciplines and Streams Modules</a> page. It also requires a level converter such as described in the <a href="../pps.html">Pulse-per-second (PPS) Signal Interfacing</a> page.</p>
<p>This driver supports all compatible receivers such as the 6-channel MX4200, MX4200D, and the 12-channel MX9212, MX9012R, MX9112.</p>
<p><a href="http://www.leica-gps.com/"><img src="../pic/9400n.jpg" alt="Leica MX9400N Navigator" height="143" width="180" align="left"></a> <a href="http://www.leica-gps.com/">Leica Geosystems</a> acquired the Magnavox commercial GPS technology business in February of 1994. They now market and support former Magnavox GPS products such as the MX4200 and its successors.</p>
<br clear="LEFT">
<p>Leica MX9400N Navigator.</p>
<h4>Operating Modes</h4>
<p>This driver supports two modes of operation, static and mobile, controlled by clock flag 2.</p>
<p>In static mode (the default) the driver assumes that the GPS antenna is in a fixed location. The receiver is initially placed in a "Static, 3D Nav" mode, where latitude, longitude, elevation and time are calculated for a fixed station. An average position is calculated from this data. After 24 hours, the receiver is placed into a "Known Position" mode, initialized with the calculated position, and then solves only for time.</p>
<p>In mobile mode, the driver assumes the GPS antenna is mounted on a moving platform such as a car, ship, or aircraft. The receiver is placed in "Dynamic, 3D Nav" mode and solves for position, altitude and time while moving. No position averaging is performed.</p>
<h4>Monitor Data</h4>
<p>The driver writes each timecode as received to the <tt>clockstats</tt> file. Documentation for the <cite>NMEA-0183</cite> proprietary sentences produced by the MX4200 can be found in <a href="../mx4200data.html">MX4200 Receiver Data Format</a>.</p>
<h4>Fudge Factors</h4>
<dl>
<dt><tt>time1 <i>time</i></tt>
<dd>Specifies the time offset calibration factor, in seconds and fraction, with default 0.0.
<dt><tt>time2 <i>time</i></tt>
<dd>Not used by this driver.
<dt><tt>stratum <i>number</i></tt>
<dd>Specifies the driver stratum, in decimal from 0 to 15, with default 0.
<dt><tt>refid <i>string</i></tt>
<dd>Specifies the driver reference identifier, an ASCII string from one to four characters, with default <tt>GPS</tt>.
<dt><tt>flag1 0 | 1</tt>
<dd>Not used by this driver.
<dt><tt>flag2 0 | 1</tt>
<dd>Assume GPS receiver is on a mobile platform if set.
<dt><tt>flag3 0 | 1</tt>
<dd>Not used by this driver.
<dt><tt>flag4 0 | 1</tt>
<dd>Not used by this driver.
</dl>
<h4>Additional Information</h4>
<p><a href="../refclock.html">Reference Clock Drivers</a> </p>
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