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diff --git a/contrib/ntp/html/driver2.htm b/contrib/ntp/html/driver2.htm deleted file mode 100644 index 885a1b2..0000000 --- a/contrib/ntp/html/driver2.htm +++ /dev/null @@ -1,137 +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>Trak 8820 GPS Receiver -</TITLE> -</HEAD> -<BODY> - -<H3> -Trak 8820 GPS Receiver</H3> - -<HR> -<H4> -Synopsis</H4> -Address: 127.127.2.<I>u</I> -<BR>Reference ID: <TT>GPS</TT> -<BR>Driver ID: <TT>GPS_TRAK</TT> -<BR>Serial Port: <TT>/dev/trak<I>u</I></TT>; 9600 baud, 8-bits, no parity -<BR>Features: <TT>tty_clk</TT> -<H4> -Description</H4> -This driver supports the Trak 8820 GPS Station Clock. The claimed accuracy -at the 1-PPS output is 200-300 ns relative to the broadcast signal; however, -in most cases the actual accuracy is limited by the precision of the timecode -and the latencies of the serial interface and operating system. - -<P>For best accuracy, this radio requires the <TT>tty_clk</TT> line discipline, -which captures a timestamp at the <TT>*</TT> on-time character of the timecode. -Using this discipline the jitter is in the order of 1 ms and systematic -error about 0.5 ms. If unavailable, the buffer timestamp is used, which -is captured at the <TT>\r</TT> ending the timecode message. This introduces -a systematic error of 23 character times, or about 24 ms at 9600 bps, together -with a jitter well over 8 ms on Sun IPC-class machines. - -<P>Using the menus, the radio should be set for 9600 bps, one stop bit -and no parity. It should be set to operate in computer (no echo) mode. -The timecode format includes neither the year nor leap-second warning. - -<P>In operation, this driver sends a <TT>RQTS\r</TT> request to the radio -at initialization in order to put it in continuous time output mode. The -radio then sends the following message once each second: -<PRE>*RQTS U,ddd:hh:mm:ss.0,q<cr><lf> - -on-time = '*' -ddd = day of year -hh:mm:ss = hours, minutes, seconds -q = quality indicator (phase error), 0-6: - 0 > 20 us - 6 > 10 us - 5 > 1 us - 4 > 100 ns - 3 > 10 ns - 2 < 10 ns</PRE> -The alarm condition is indicated by <TT>0</TT> at <TT>Q</TT>, which means -the radio has a phase error greater than 20 us relative to the broadcast -time. The absence of year, DST and leap-second warning in this format is -also alarmed. - -<P>The continuous time mode is disabled using the <TT>RQTX\r</TT> request, -following which the radio sends a <TT>RQTX DONE<cr><lf></TT> response. -In the normal mode, other control and status requests are effective, including -the leap-second status request <TT>RQLS<cr></TT>. The radio responds -with <TT>RQLS yy,mm,dd<cr><lf></TT>, where <TT>yy,mm,dd</TT> are -the year, month and day. Presumably, this gives the epoch of the next leap -second, <TT>RQLS 00,00,00</TT> if none is specified in the GPS message. -Specified in this form, the information is generally useless and is ignored -by the driver. -<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, -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> - - -<P>Additional Information - -<P><A HREF="refclock.htm">Reference Clock Drivers</A></DL> - -<HR> -<ADDRESS> -David L. Mills (mills@udel.edu)</ADDRESS> - -</BODY> -</HTML> |
