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diff --git a/contrib/ntp/html/driver5.htm b/contrib/ntp/html/driver5.htm deleted file mode 100644 index edbd045..0000000 --- a/contrib/ntp/html/driver5.htm +++ /dev/null @@ -1,159 +0,0 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="GENERATOR" CONTENT="Mozilla/4.01 [en] (Win95; I) [Netscape]"> - <TITLE>TrueTime GPS/GOES/OMEGA Receivers -</TITLE> -</HEAD> -<BODY> - -<H3> -TrueTime GPS/GOES/OMEGA Receivers</H3> - -<HR> -<H4> -Synopsis</H4> -Address: 127.127.5.<I>u</I> -<BR>Reference ID: <TT>GPS, OMEGA, GOES</TT> -<BR>Driver ID: <TT>TRUETIME</TT> -<BR>Serial Port: <TT>/dev/true<I>u</I></TT>; 9600 baud, 8-bits, no parity -<BR>Features: <TT>tty_clk</TT> -<H4> -Description</H4> -This driver supports several models models of Kinemetrics/TrueTime timing -receivers, including 468-DC MK III GOES Synchronized Clock, GPS- DC MK -III and GPS/TM-TMD GPS Synchronized Clock, XL-DC (a 151-602-210, reported -by the driver as a GPS/TM-TMD), GPS-800 TCU (an 805-957 with the RS232 -Talker/Listener module), OM-DC OMEGA Synchronized Clock, and very likely -others in the same model family that use the same timecode formats. - -<P>Most of this code is originally from refclock_wwvb.c with thanks. It -has been so mangled that wwvb is not a recognizable ancestor. -<PRE>Timcode format: ADDD:HH:MM:SSQCL - -A - control A (this is stripped before we see it) -Q - Quality indication (see below) -C - Carriage return -L - Line feed - -Quality codes indicate possible error of - - 468-DC GOES Receiver: - GPS-TM/TMD Receiver: - ? +/- 500 milliseconds # +/- 50 milliseconds - * +/- 5 milliseconds . +/- 1 millisecond - space less than 1 millisecond - - OM-DC OMEGA Receiver: - - > +/- 5 seconds - - ? +/- 500 milliseconds # +/- 50 milliseconds - * +/- 5 milliseconds . +/- 1 millisecond - - A-H less than 1 millisecond. Character indicates which -station - is being received as follows: A = Norway, B = Liberia, - C = Hawaii, D = North Dakota, E = La Reunion, F = -Argentina, - G = Australia, H = Japan.</PRE> -The carriage return start bit begins on 0 seconds and extends to 1 bit -time. - -<P>Notes on 468-DC and OMEGA receiver: - -<P>Send the clock a <TT>R</TT> or <TT>C</TT> and once per second a timestamp -will appear. Send a <TT>R</TT> to get the satellite position once (GOES -only). - -<P>Notes on the 468-DC receiver: - -<P>Since the old east/west satellite locations are only historical, you -can't set your clock propagation delay settings correctly and still use -automatic mode. The manual says to use a compromise when setting the switches. -This results in significant errors. The solution; use fudge time1 and time2 -to incorporate corrections. If your clock is set for 50 and it should be -58 for using the west and 46 for using the east, use the line - -<P><TT>fudge 127.127.5.0 time1 +0.008 time2 -0.004</TT> - -<P>This corrects the 4 milliseconds advance and 8 milliseconds retard needed. -The software will ask the clock which satellite it sees. - -<P>The PCL720 from PC Labs has an Intel 8253 look-alike, as well as a bunch -of TTL input and output pins, all brought out to the back panel. If you -wire a PPS signal (such as the TTL PPS coming out of a GOES or other Kinemetrics/Truetime -clock) to the 8253's GATE0, and then also wire the 8253's OUT0 to the PCL720's -INPUT3.BIT0, then we can read CTR0 to get the number of microseconds since -the last PPS upward edge, mediated by reading OUT0 to find out if the counter -has wrapped around (this happens if more than 65535us (65ms) elapses between -the PPS event and our being called.) -<H4> -Monitor Data</H4> -When enabled by the <TT>flag4</TT> fudge flag, every received timecode -is written as-is to the <TT>clockstats</TT> file. -<H4> -Fudge Factors</H4> - -<DL> -<DT> -<TT>time1 <I>time</I></TT></DT> - -<DD> -Specifies the time offset calibration factor, in seconds and fraction, -to be used for the West satellite, with default 0.0.</DD> - -<DT> -<TT>time2 <I>time</I></TT></DT> - -<DD> -. Specifies the time offset calibration factor, in seconds and fraction, -to be used for the East satellite, with default 0.0.</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>TRUE</TT>.</DD> - -<DT> -<TT>flag1 0 | 1</TT></DT> - -<DD> -Silence the clock side of ntpd, just reading the clock without trying to -write to it.</DD> - -<DT> -<TT>flag2 0 | 1</TT></DT> - -<DD> -Generate a debug file /tmp/true%d.</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> -Additional Information - -<P><A HREF="refclock.htm">Reference Clock Drivers</A> -<HR> -<ADDRESS> -David L. Mills (mills@udel.edu)</ADDRESS> - -</BODY> -</HTML> |
