mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-21 11:13:30 +00:00
99 lines
2.3 KiB
HTML
99 lines
2.3 KiB
HTML
<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>KSI/Odetics TPRO/S IRIG Interface
|
|
</TITLE>
|
|
</HEAD>
|
|
<BODY>
|
|
|
|
<H3>
|
|
KSI/Odetics TPRO/S IRIG Interface</H3>
|
|
|
|
<HR>
|
|
<H4>
|
|
Synopsis</H4>
|
|
Address: 127.127.12.<I>u</I>
|
|
<BR>Reference ID: <TT>IRIG</TT>
|
|
<BR>Driver ID: <TT>IRIG_TPRO</TT>
|
|
<BR>TPRO Device: <TT>/dev/tpro<I>u</I></TT>
|
|
<BR>Requires: KSI/Odetics device driver, <TT>/usr/include/sys/tpro.h</TT> header file
|
|
<H4>
|
|
Description</H4>
|
|
This driver supports the KSI/Odetics TPRO and TPRO-SAT IRIG-B Decoder,
|
|
which is a module connected directly to the SBus of a Sun workstation.
|
|
The module works with the IRIG-B signal generated by several radio clocks,
|
|
including those made by Arbiter, Austron, Odetics, Spectracom and TrueTime,
|
|
among others, although it is generally an add- on option. In the case of
|
|
the TPRO-SAT, the module is an integral part of a GPS receiver, which serves
|
|
as the primary timing source.
|
|
|
|
<P>Using the TPRO interface as a NTP reference clock provides precision
|
|
time only to ntpd and its clients. With suitable kernel modifications,
|
|
it is possible to use the TPRO as the CPU system clock, avoiding errors
|
|
introduced by the CPU clock oscillator wander. See the <A HREF="kern.htm">A
|
|
Kernel Model for Precision Timekeeping </A>page for further details.
|
|
<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>IRIG</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>
|
|
Additional Information
|
|
|
|
<P><A HREF="refclock.htm">Reference Clock Drivers</A>
|
|
<HR>
|
|
<ADDRESS>
|
|
David L. Mills (mills@udel.edu)</ADDRESS>
|
|
|
|
</BODY>
|
|
</HTML>
|