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diff --git a/contrib/ntp/html/driver30.htm b/contrib/ntp/html/driver30.htm deleted file mode 100644 index d2ec9dd..0000000 --- a/contrib/ntp/html/driver30.htm +++ /dev/null @@ -1,190 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859- -1"> - <META NAME="GENERATOR" CONTENT="Mozilla/4.06 [en] (X11; I; FreeBSD -3.0-CURRENT i386) [Netscape]"> - <TITLE>Motorola Oncore GPS Receiver -</TITLE> -</HEAD> -<BODY> - -<H3> -Motorola Oncore GPS receiver</H3> - -<HR> -<H4> -Synopsis</H4> - -Address: 127.127.30.<i>u</i><BR> -Reference ID: <TT>GPS</TT><BR> -Driver ID: ONCORE<BR> -Serial Port: <TT>/dev/oncore.serial.</TT><i>u</i>; 9600 baud, 8-bits, -no parity.<BR> -PPS Port: <TT>/dev/oncore.pps.</TT><i>u</i>; <TT>PPS_CAPTUREASSERT</TT> -required, <TT>PPS_OFFSETASSERT</TT> supported.<BR> -Configuration File: <TT>/etc/ntp.oncore<TT><i>u</i> or, -<TT>/etc/ntp.oncore.<TT><i>u</i>, or <TT>/etc/ntp.oncore<TT>. -<H4> -Description</H4> -This driver supports most models of the -<A HREF="http://www.mot.com/AECS/PNSB/products">Motorola Oncore GPS receivers</A> -(Basic, PVT6, VP, UT, UT+, GT, GT+, SL, M12), -as long as they support the <I>Motorola Binary Protocol</I>. - -<P>The three most interesting versions of the Oncore are the VP, -the UT+, and the "Remote" which is a prepackaged UT+. -The VP is no longer available. -The Motorola evaluation kit -can also be recommended, it interfaces to a PC straightaway, using the -serial (DCD) or parallel port for PPS input and packs the -receiver in a nice and sturdy box. -Two less expensive interface kits are available from -<A HREF="http://www.tapr.org">TAPR</A>. - -<BR> -<CENTER><TABLE NOSAVE > -<TR NOSAVE> -<TD NOSAVE><IMG SRC="pic/oncore_utplusbig.gif" HEIGHT=124 -WIDTH=210></TD> - -<TD><IMG SRC="pic/oncore_evalbig.gif" HEIGHT=124 WIDTH=182></TD> - -<TD><IMG SRC="pic/oncore_remoteant.jpg" HEIGHT=188 WIDTH=178></TD> -</TR> - -<TR> -<TD> -<CENTER>UT+ oncore</CENTER> -</TD> - -<TD> -<CENTER>Evaluation kit</CENTER> -</TD> - -<TD> -<CENTER>Oncore Remote</CENTER> -</TD> -</TR> -</TABLE></CENTER> - -<P>The driver requires a standard <TT>PPS</TT> interface for the -pulse-per-second output from the receiver. The serial data stream alone -does not provide precision time stamps (0-50msec variance, according to -the manual), whereas the PPS output is precise down to 50 nsec (1 sigma) -for the VP/UT models. -If you do not have the PPS signal available, then you should probably be using -the NMEA driver rather than the Oncore driver. - -<P>The driver will use the "position hold" mode with -user provided coordinates, -the receivers built-in site-survey, -or a similar algorithm implemented in this driver to determine the antenna position. -<H4> -Monitor Data</H4> -The driver always puts a lot of useful information on the clockstats file, -and when run with debugging can be quite chatty on stdout. -When first starting to use the driver you should definitely review the information -written to the clockstats file to verify that the driver is running correctly. -<P> -In addition, on platforms supporting Shared Memory, all of the messages -received from the Oncore receiver are made available in shared memory for -use by other programs. -See the <A HREF=Oncore-SHMEM.htm> Oncore-SHMEM </A> manual page for -information on how to use this option. -For either debugging or using the SHMEM option, an Oncore Reference Manual -for the specific receiver in use will be required. -<H4> -Fudge Factors</H4> - -<DL> -<DT> -<TT>time1 <I>time</I></TT></DT> - -<DD> -Specifies the time offset calibration factor, in seconds and fraction, -with default 0.0.</DD> - -<DT> -<TT>time2 <I>time</I></TT></DT> - -<DD> -Not used by this driver.</DD> - -<DT> -<TT>stratum <I>number</I></TT></DT> - -<DD> -Specifies the driver stratum, in decimal from 0 to 15, with default -0.</DD> - -<DT> -<TT>refid <I>string</I></TT></DT> - -<DD> -Specifies the driver reference identifier, an ASCII string from one to -four characters, with default <TT>GPS</TT>.</DD> - -<DT> -<TT>flag1 0 | 1</TT></DT> - -<DD> -Not used by this driver.</DD> - -<DT> -<TT>flag2 0 | 1</TT></DT> - -<DD> -Not used by this driver.</DD> - -<DT> -<TT>flag3 0 | 1</TT></DT> - -<DD> -Not used by this driver.</DD> - -<DT> -<TT>flag4 0 | 1</TT></DT> - -<DD> -Not used by this driver.</DD> -</DL> -<B>Additional Information</B> -<P>The driver was initially developed on FreeBSD, and has since been tested -on Linux, SunOS and Solaris. -<P><B>Configuration</B> -<P>There is a driver specific configuration file <TT>/etc/ntp.oncore</TT> -that contains information on the startup mode, the location of the GPS -receiver, an offset of the PPS signal from zero, and the cable delay. -The offset shifts the PPS signal to avoid interrupt pileups `on' the second, -and adjust the timestamp accordingly. -See the driver source for information on this file. -The default with no file is: no delay, no offset, and a site survey is done -to get the location of the gps receiver. - -<P>The <TT>/etc/ntp.conf</TT> file will need a line of the form<BR> - -<TT> pps /dev/oncore.pps.0 [ assert/clear ] hardpps</TT><BR> -if you want the oncore driver to control the kernel PLL. -For more information, see the <A HREF=clockopt.htm>Reference Clock -Options</A> page. - -<P><B>Performance</B> -<P>Really good. With the VP/UT+, the generated PPS pulse is referenced -to UTC(GPS) with better than 50 nsec (1 sigma) accuracy. The -limiting factor will be the timebase of the computer and the precision -with which you can timestamp the rising flank of the -PPS signal. -Using FreeBSD, a FPGA based Timecounter/PPS interface, -and an ovenized quartz oscillator, that performance has been reproduced. - For more details on this aspect: <A -HREF="http://phk.freebsd.dk/rover.html">Sub-Microsecond -timekeeping under FreeBSD</A>. -<HR> -<ADDRESS> -Poul-Henning Kamp (phk@FreeBSD.org), -Reg Clemens (reg@dwf.com) -</ADDRESS> -</BODY> -</HTML> |
