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Magnavox MX4200 GPS Receiver
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Magnavox MX4200 GPS Receiver
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<p><h4>Synopsis</h4>

<p>Address: 127.127.9.<var>u</var>
<br>Reference ID: GPS
<br>Driver ID: GPS-MX4200
<br>Serial Port: <code>/dev/gps<var>u</var></code>; 4800 baud, 8-bits,
no parity
<br>Features: <code>ppsclock</code> (required)

<p><h4>Description</h4>

<p>This driver supports the Magnavox MX 4200 Navigation Receiver adapted
to precision timing applications. It requires the <code>ppsclock</code>
line discipline or streams module described in the <a
href="ldisc.html">Line Disciplines and Streams Drivers</a> page. It also
requires a gadget box and 1-PPS level converter, such as described in
the <a href="pps.html">Pulse-per-second (PPS) Signal Interfacing</a>
page.

<p>This driver supports all compatible receivers such as the 6-channel
MX 4200, MX 4200D, and the 12-channel MX 9212, MX 9012R, MX 9112.

<p><h4>Operating Modes</h4>
  
<p>This driver supports two modes of operation, static and mobile,
controlled by clock flag 2.

<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.  A DOP-weighted running 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.  The position averaging algorithm does
not take into account boundary conditions, so this mode of operation
very near the international date line or the poles is not recommended.

<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
<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.

<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>GPS</code>.

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

<p><dt><code>flag2 0 | 1</code>
<dd>Assume GPS receiver is on a mobile platform if set.

<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>
