diff options
author | roberto <roberto@FreeBSD.org> | 2002-11-04 19:36:11 +0000 |
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committer | roberto <roberto@FreeBSD.org> | 2002-11-04 19:36:11 +0000 |
commit | a85d9ae25e8e8696677bc30feb6eaf7fc150e529 (patch) | |
tree | 5071c8dbfd7605eec15909cabca2296957573ac7 /contrib/ntp/html | |
parent | 8d541346f2b91896a9ef53cafe2b81898978ccf3 (diff) | |
download | FreeBSD-src-a85d9ae25e8e8696677bc30feb6eaf7fc150e529.zip FreeBSD-src-a85d9ae25e8e8696677bc30feb6eaf7fc150e529.tar.gz |
Virgin import of ntpd 4.1.1b
Diffstat (limited to 'contrib/ntp/html')
-rw-r--r-- | contrib/ntp/html/driver42.htm | 41 | ||||
-rw-r--r-- | contrib/ntp/html/driver43.htm | 109 | ||||
-rwxr-xr-x | contrib/ntp/html/driver44.htm | 131 | ||||
-rw-r--r-- | contrib/ntp/html/refclock.htm | 430 |
4 files changed, 470 insertions, 241 deletions
diff --git a/contrib/ntp/html/driver42.htm b/contrib/ntp/html/driver42.htm new file mode 100644 index 0000000..655ff14 --- /dev/null +++ b/contrib/ntp/html/driver42.htm @@ -0,0 +1,41 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 3.2//EN"> +<html> +<head> +<meta name="generator" content= +"HTML Tidy for Solaris (vers 1st May 2002), see www.w3.org"> +<meta http-equiv="Content-Type" content= +"text/html; charset=iso-8859-1"> +<meta name="GENERATOR" content= +"Mozilla/4.01 [en] (Win95; I) [Netscape]"> +<title>Zyfer GPStarplus Receiver</title> +</head> +<body> +<h3>Zyfer GPStarplus Receiver</h3> + +<hr> +<h4>Synopsis</h4> + +Address: 127.127.42.<i>u</i> <br> +Reference ID: <tt>GPS</tt> <br> +Driver ID: <tt>Zyfer GPStarplus</tt> <br> +Serial Port: <tt>/dev/zyfer<i>u</i></tt>; 9600 baud, 8-bits, no +parity <br> +Features: <tt>(none)</tt> +<h4>Description</h4> + +This driver supports the <a href="http://www.zyfer.com/">Zyfer +GPStarplus</a> receiver. +<p>The receiver has a DB15 port on the back which has input TxD and +RxD lines for configuration and control, and a separate TxD line +for the once-per-second timestamp.</p> + +<p>Additionally, there are BNC connectors on the back for things +like PPS and IRIG output. Additional Information</p> + +<p><a href="refclock.htm">Reference Clock Drivers</a> </p> + +<hr> +<address>Harlan Stenn (stenn@whimsy.udel.edu)</address> +</body> +</html> + diff --git a/contrib/ntp/html/driver43.htm b/contrib/ntp/html/driver43.htm new file mode 100644 index 0000000..fc994ef --- /dev/null +++ b/contrib/ntp/html/driver43.htm @@ -0,0 +1,109 @@ +<html> +<head> +<title>RIPE NCC interface for Trimble Palisade</title> +</head> +<body> +<h3>RIPE NCC interface for Trimble Palisade</h3> + +<hr> + +<img src="pic/driver43_2.jpg" alt="Trimble Acutime 2000" align="right"> + +<h4>Synopsis</h4> + +Address: 127.127.43.<i>u</i> <br> +Reference ID: <tt>RIPENCC</tt> <br> +Driver ID: <tt>RIPENCC</tt> + +<h4>Description</h4> + +<p> This is a special driver developed to be used in conjuction with the +RIPE NCC clock card in the RIPE NCC Test Traffic Measurements project. +</p> + +<h4>Why this driver?</h4> + +<p> +The reason why we created a seperated driver for an antenna for which +already a (vendor supplied) driver exist is a design decision. +To be more specific, the standard Trimble interface uses a 12 pin +connector. The cable sold by Trimble to connect to this wire is a very +thick cable. Certainly not something you wish to run for several 100 +meters through your building. And if you wanted to run it for 100 meters, +you always would have to really run the cable, and didn't have the option +to use existing wiring.<br> +This is where we wanted more flexibility. We wanted to be able to use +existing wiring in buildings. That leaded us to CAT-5(UTP) which only +gives us 8 wires. Therefor we decided to redesing the use of the Trimble +antenna. The Trimble supports two modes: EVENT driver and PPS mode. The +default is to use the EVENT mode which needs all 12 wires. We only use the +PPS timestamps for which we have enough with 8 wires. For our purposes +this is more than fine. +</p> + +More information about the project can be found on the <a href="http://www.ripe.net/test-traffic" TARGET=_new>Test Traffic Measurements</a> website. + +<img src="pic/driver43_1.gif" alt="RIPE NCC clock card" align="right"> +<h4> RIPE NCC clock card</h4> + +<p>The card is very a simple PCI card. The only feature on the bus it uses +is the power supply. It uses this power supply to power the Trimble GPS +antenna.</p> + +<p>The card basicly just is a RS422 to RS232 converter. It gets the +Trimble's RS422 signal on a RJ45 connector and transforms that to RS232 on a +DIN9 connector. This connector should be loopbacked on the back of the +machine to the serial port. As said, the card doesn't do any PCI data +transfers.</p> + +<p>The schematics of the interface card is available here: <a +href="http://www.ripe.net/ripencc/mem-services/ttm/Documents/gps_interface_schematic.pdf">gps_interface_schematic.pdf</a>. +You are free to create this card yourself as long as you give some credit +or reference to us. Note that we don't sell these cards on a commercial +basis, but for interested parties we do have some spares to share.<p> + + +<h4>Monitor Data</h4> + +In the <tt>filegen clockstats</tt> file the following (example) data is +collected: +<pre> +52445 41931.275 127.127.40.0 U1 20.6.2002 11:38:51 13 11 +52445 41931.395 127.127.40.0 C1 20062002 113851 6 364785 110.2 450 6.7 13 5222.374737 N 0453.268013 E 48 7 11 0 1 -14 20 0 -25 +52445 41931.465 127.127.40.0 S1 07 1 1 02 59.3 291.5 39.3 +52445 41931.485 127.127.40.0 S1 11 2 1 02 59.9 138.0 60.2 +52445 41931.525 127.127.40.0 S1 01 4 1 02 48.4 185.7 28.3 +52445 41931.555 127.127.40.0 S1 14 5 2 02 32.7 41.0 15.4 +52445 41931.585 127.127.40.0 S1 20 6 1 02 59.9 256.6 78.0 +52445 41931.615 127.127.40.0 S1 25 8 2 00 0.0 86.6 20.1 +</pre> +This is in the form of: +<pre> +All output lines consist of a prefix and a message, the prefix is: +[days since epoch] [sec.ms since start of day] [peer address] + +And all individual messages: + +*Primary UTC time packet: +U1 [date] [time] [trackstat] [utcflags] + +*Comprehensive time packet: +C1 [date] [time] [mode] [bias] [biasunc] [rate] [rateunc] [utcoff] [latitude] [longtitude] [alt] [vis sat](x8) + +*Tracking status packet: +S1 [prn] [channel] [aqflag] [ephstat] [snr] [azinuth] [elevation] +</pre> + +<h4>Additional Information</h4> + +<a href="refclock.htm">Reference Clock Drivers</a> + + +<hr> +<a href="index.htm"><img align="left" src="pic/home.gif" alt= +"Home"></a> + +<address><a href="mailto:marks@ripe.net">Mark Santcroos +<marks@ripe.net></a></address> +</body> +</html> diff --git a/contrib/ntp/html/driver44.htm b/contrib/ntp/html/driver44.htm new file mode 100755 index 0000000..0d29384 --- /dev/null +++ b/contrib/ntp/html/driver44.htm @@ -0,0 +1,131 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+<html>
+<head>
+ <title>NeoClock4X</title>
+
+ <meta http-equiv="content-type"
+ content="text/html; charset=ISO-8859-15">
+</head>
+ <body>
+
+<h1>NeoClock4X - DCF77 / TDF serial line receiver<br>
+ </h1>
+
+<hr width="100%" size="2">
+<h2>Synopsis</h2>
+
+<table cellpadding="0" cellspacing="0" border="0" width="100%">
+ <tbody>
+ <tr>
+ <td valign="top">
+ <table cellpadding="2" cellspacing="0" border="0" width="100%">
+ <tbody>
+ <tr>
+ <td valign="top">Adress<br>
+ </td>
+ <td valign="top">127.127.44.u<br>
+ </td>
+ </tr>
+ <tr>
+ <td valign="top">Reference ID<br>
+ </td>
+ <td valign="top">neol<br>
+ </td>
+ </tr>
+ <tr>
+ <td valign="top">Driver ID<br>
+ </td>
+ <td valign="top">NEOCLK4X<br>
+ </td>
+ </tr>
+ <tr>
+ <td valign="top">Serial Port<br>
+ </td>
+ <td valign="top">/dev/neoclock4x-u<br>
+ </td>
+ </tr>
+
+ </tbody>
+ </table>
+ <br>
+ </td>
+ <td valign="top" align="right"><a href="http://www.linum.com"><img
+ src="pic/neoclock4x.gif" alt="NeoClock4X - DCF77 receiver" width="150"
+ height="195">
+ </a><br>
+ </td>
+ </tr>
+
+ </tbody>
+</table>
+
+<hr width="100%" size="2">
+<h2>Description</h2>
+ The refclock_neoclock4x driver supports the NeoClock4X receiver available
+ from <a href="http://www.linum.com">Linum Software GmbH</a>. The receiver
+ is available as a <a href="http://www.dcf77.de">DCF77</a> or TDF receiver.
+ Both receivers have the same output string. For more information about the
+ NeoClock4X receiver please visit <a
+ href="http://www.linum.com/redir/jump/id=neoclock4x&action=redir">http://www.linum.com/redir/jump/id=neoclock4x&action=redir</a>.
+
+<hr width="100%" size="2">
+<h2>Fudge Factors</h2>
+
+<dl>
+ <dt> <b><a href="clockopt.htm">time1 time</a></b></dt>
+ <dd> Specifies the time offset calibration factor with the default value
+ off 0.16958333 seconds. This offset is used to correct serial line and
+operating system delays incurred in capturing time stamps. If you want to
+fudge the time1 offset <b>ALWAYS</b> add a value off 0.16958333. This is
+neccessary to compensate to delay that is caused by transmit the timestamp
+at 2400 Baud. If you want to compensate the delay that the DCF77 or TDF radio
+signal takes to travel to your site simply add the needed millisecond delay
+to the given value. Note that the time here is given in seconds.</dd>
+ <dd>Default setting is 0.16958333 seconds.<br>
+ </dd>
+</dl>
+
+<dl>
+ <dt> <b><a href="file:///E:/ntp-4.1.1a/html/clockopt.htm">time2 time</a></b></dt>
+ <dd> Not used by this driver.</dd>
+</dl>
+
+<dl>
+ <dt> <a href="clockopt.htm"><b>flag1 0 | 1</b></a></dt>
+ <dd>When set to 1 the driver will feed ntp with timestampe even if the
+radio signal is lost. In this case an internal backup clock generates the
+timestamps. This is ok as long as the receiver is synced once since the receiver
+is able to keep time for a long period.</dd>
+ <dd>Default setting is 0 = don't synchronize to CMOS clock.<br>
+ </dd>
+ <dd><br>
+ </dd>
+ <dt> <a href="clockopt.htm"><b>flag2 0 | 1</b></a></dt>
+ <dd>You can allow the NeoClock4X driver to use the quartz clock even if
+ it is never synchronized to a radio clock. This is usally not a good idea
+ if you want preceise timestamps since the CMOS clock is maybe not adjusted
+ to a dst status change. So <b>PLEASE</b> switch this only on if you now
+what you're doing.</dd>
+ <dd>Default setting is 0 = don't synchronize to unsynchronized CMOS clock.<br>
+ </dd>
+ <dt><br>
+ </dt>
+ <dt><a href="clockopt.htm"><b>flag3 0 | 1</b></a></dt>
+ <dd> Not used by this driver.<tt><tt><tt><tt><tt><tt> </tt></tt></tt></tt></tt></tt></dd>
+ <dd><br>
+ </dd>
+ <dt> <a href="clockopt.htm"><b>flag4 0 | 1</b></a></dt>
+ <dd>It is recommended to allow extensive logging while you setup the NeoClock4X
+ receiver. If you activate flag4 every received data is logged. You should
+ turn off flag4 as soon as the clock works as expected to reduce logfile
+cluttering.</dd>
+ <dd>Default setting is 0 = don't log received data and converted utc time.<br>
+ </dd>
+</dl>
+
+<hr width="100%" size="2">Please send any comments or question to <a
+ href="mailto:neoclock4@linum.com">neoclock4x@linum.com</a>.<br>
+ <br>
+ <br>
+</body>
+</html>
diff --git a/contrib/ntp/html/refclock.htm b/contrib/ntp/html/refclock.htm index 079baba..df4af3a 100644 --- a/contrib/ntp/html/refclock.htm +++ b/contrib/ntp/html/refclock.htm @@ -1,254 +1,202 @@ <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"> <html> <head> -<meta name="generator" content="HTML Tidy, see www.w3.org"> -<title>Reference Clock Drivers</title> + + <meta name="generator" content="HTML Tidy, see www.w3.org"> + <title>Reference Clock Drivers</title> </head> -<body> + <body> + <h3>Reference Clock Drivers</h3> - -<img align="left" src="pic/stack1a.jpg" alt="gif">Master Time -Facility at the <a href="http://www.eecis.udel.edu/~mills/lab.htm"> -UDel Internet Research Laboratory</a>: <br clear="left"> -<hr> -<p>Support for most of the commonly available radio and modem -reference clocks is included in the default configuration of the -NTP daemon for Unix <tt>ntpd</tt>. Individual clocks can be -activated by configuration file commands, specifically the <tt> -server</tt> and <tt>fudge</tt> commands described in the <a href= -"ntpd.htm"><tt>ntpd</tt> program manual page</a>. The following -discussion presents Information on how to select and configure the -device drivers in a running Unix system.</p> - -<p>Many radio reference clocks can be set to display local time as -adjusted for timezone and daylight saving mode. For use with NTP -the clock must be set for Coordinated Universal Time (UTC) only. -Ordinarily, these adjustments are performed by the kernel, so the -fact that the clock runs on UTC will be transparent to the -user.</p> - -<p>Radio and modem clocks by convention have addresses in the form -127.127.<i>t.u</i>, where <i>t</i> is the clock type and <i>u</i> -is a unit number in the range 0-3 used to distinguish multiple -instances of clocks of the same type. Most of these clocks require -support in the form of a serial port or special bus peripheral, but -some can work directly from the audio codec found in some -workstations. The particular device is normally specified by adding -a soft link <tt>/dev/device<i>u</i></tt> to the particular hardware -device involved, where <i><tt>u</tt></i> correspond to the unit -number above.</p> - -<p>Most clock drivers communicate with the reference clock using a -serial port, usually at 9600 bps. There are several application -program interfaces (API) used in the various Unix and NT systems, -most of which can be detected at configuration time. Thus, it is -important that the NTP daemon and utilities be compiled on the -target system or clone. In some cases special features are -available, such as timestamping in the kernel or pulse-per-second -(PPS) interface. In most cases these features can be detected at -configuration time as well; however, the kernel may have to be -recompiled in order for them to work.</p> - -<p>The audio drivers are a special case. These include support for -the NIST time/frequency stations WWV and WWVH, the Canadian -time/frequency station CHU and generic IRIG signals. Currently, -support for the Solaris and SunOS audio API is included in the -distribution. It is left to the volunteer corps to extend this -support to other systems. Further information on hookup, debugging -and monitoring is given in the <a href="audio.htm">Audio -Drivers</a> page.</p> - -<p>The local clock driver is also a special case. A server -configured with this driver can operate as a primary server to -synchronize other clients when no other external synchronization -sources are available. If the server is connected directly or -indirectly to the public Internet, there is some danger that it can -adversely affect the operation of unrelated clients. Carefully read -the <a href="driver1.htm">Undisciplined Local Clock</a> page and -respect the stratum limit.</p> - -<p>The local clock driver also supports an external synchronization -source such as a high resolution counter disciplined by a GPS -receiver, for example. Further information is on the <a href= -"extern.htm">External Clock Discipline and the Local Clock -Driver</a> page.</p> - + <img align="left" src="pic/stack1a.jpg" alt="gif"> +Master Time Facility at the <a + href="http://www.eecis.udel.edu/%7Emills/lab.htm"> UDel Internet Research +Laboratory</a>: <br clear="left"> + +<hr> +<p>Support for most of the commonly available radio and modem reference clocks +is included in the default configuration of the NTP daemon for Unix <tt>ntpd</tt>. +Individual clocks can be activated by configuration file commands, specifically +the <tt> server</tt> and <tt>fudge</tt> commands described in the <a + href="ntpd.htm"><tt>ntpd</tt> program manual page</a>. The following discussion +presents Information on how to select and configure the device drivers in +a running Unix system.</p> + +<p>Many radio reference clocks can be set to display local time as adjusted +for timezone and daylight saving mode. For use with NTP the clock must be +set for Coordinated Universal Time (UTC) only. Ordinarily, these adjustments +are performed by the kernel, so the fact that the clock runs on UTC will +be transparent to the user.</p> + +<p>Radio and modem clocks by convention have addresses in the form 127.127.<i>t.u</i>, +where <i>t</i> is the clock type and <i>u</i> is a unit number in the range +0-3 used to distinguish multiple instances of clocks of the same type. Most +of these clocks require support in the form of a serial port or special bus +peripheral, but some can work directly from the audio codec found in some +workstations. The particular device is normally specified by adding a soft +link <tt>/dev/device<i>u</i></tt> to the particular hardware device involved, +where <i><tt>u</tt></i> correspond to the unit number above.</p> + +<p>Most clock drivers communicate with the reference clock using a serial +port, usually at 9600 bps. There are several application program interfaces +(API) used in the various Unix and NT systems, most of which can be detected +at configuration time. Thus, it is important that the NTP daemon and utilities +be compiled on the target system or clone. In some cases special features +are available, such as timestamping in the kernel or pulse-per-second (PPS) +interface. In most cases these features can be detected at configuration +time as well; however, the kernel may have to be recompiled in order for +them to work.</p> + +<p>The audio drivers are a special case. These include support for the NIST +time/frequency stations WWV and WWVH, the Canadian time/frequency station +CHU and generic IRIG signals. Currently, support for the Solaris and SunOS +audio API is included in the distribution. It is left to the volunteer corps +to extend this support to other systems. Further information on hookup, debugging +and monitoring is given in the <a href="audio.htm">Audio Drivers</a> page.</p> + +<p>The local clock driver is also a special case. A server configured with +this driver can operate as a primary server to synchronize other clients +when no other external synchronization sources are available. If the server +is connected directly or indirectly to the public Internet, there is some +danger that it can adversely affect the operation of unrelated clients. Carefully +read the <a href="driver1.htm">Undisciplined Local Clock</a> page and respect +the stratum limit.</p> + +<p>The local clock driver also supports an external synchronization source +such as a high resolution counter disciplined by a GPS receiver, for example. +Further information is on the <a href="extern.htm">External Clock Discipline +and the Local Clock Driver</a> page.</p> + <h4>Driver Calibration</h4> - -<p>Some drivers depending on longwave and shortwave radio services -need to know the radio propagation time from the transmitter to the -receiver, which can amount to some tens of milliseconds. This must -be calculated for each specific receiver location and requires the -geographic coordinates of both the transmitter and receiver. The -transmitter coordinates for various radio services are given in the -<a href="qth.htm">Stations, Frequencies and Geographic -Coordinates</a> page. Receiver coordinates can be obtained or -estimated from various sources. The actual calculations are beyond -the scope of this document.</p> - -<p>When more than one clock driver is supported, it is often the -case that each shows small systematic offset differences relative -to the rest. To reduce the effects of jitter when switching from -one driver to the another, it is useful to calibrate the drivers to -a common ensemble offset. The <tt>enable calibrate</tt> -configuration command in the <a href="miscopt.htm">Miscellaneous -Options</a> page is useful for this purpose. The calibration -function can also be enabled and disabled using the <tt>ntpdc</tt> -program utility.</p> - -<p>Most clock drivers use the <tt>time1</tt> value specified in the -<tt>fudge</tt> configuration command to provide the calibration -correction when this cannot be provided by the clock or interface. -When the calibration function is enabled, the <tt>time1</tt> value -is automatically adjusted to match the offset of the remote server -or local clock driver selected for synchronization. Ordinarily, the -NTP selection algorithm chooses the best from among all sources, -usually the best radio clock determined on the basis of stratum, -synchronization distance and jitter. The calibration function -adjusts the <tt>time1</tt> values for all clock drivers except this -source so that their indicated offsets tend to zero. If the -selected source is the kernel PPS discipline, the <tt>fudge + +<p>Some drivers depending on longwave and shortwave radio services need to +know the radio propagation time from the transmitter to the receiver, which +can amount to some tens of milliseconds. This must be calculated for each +specific receiver location and requires the geographic coordinates of both +the transmitter and receiver. The transmitter coordinates for various radio +services are given in the <a href="qth.htm">Stations, Frequencies and Geographic +Coordinates</a> page. Receiver coordinates can be obtained or estimated from +various sources. The actual calculations are beyond the scope of this document.</p> + +<p>When more than one clock driver is supported, it is often the case that +each shows small systematic offset differences relative to the rest. To reduce +the effects of jitter when switching from one driver to the another, it is +useful to calibrate the drivers to a common ensemble offset. The <tt>enable +calibrate</tt> configuration command in the <a href="miscopt.htm">Miscellaneous +Options</a> page is useful for this purpose. The calibration function can +also be enabled and disabled using the <tt>ntpdc</tt> program utility.</p> + +<p>Most clock drivers use the <tt>time1</tt> value specified in the <tt>fudge</tt> +configuration command to provide the calibration correction when this cannot +be provided by the clock or interface. When the calibration function is enabled, +the <tt>time1</tt> value is automatically adjusted to match the offset of +the remote server or local clock driver selected for synchronization. Ordinarily, +the NTP selection algorithm chooses the best from among all sources, usually +the best radio clock determined on the basis of stratum, synchronization +distance and jitter. The calibration function adjusts the <tt>time1</tt> +values for all clock drivers except this source so that their indicated offsets +tend to zero. If the selected source is the kernel PPS discipline, the <tt>fudge time1</tt> values for all clock drivers are adjusted.</p> - -<p>The adjustment function is an exponential average designed to -improve accuracy, so the function takes some time to converge. The -recommended procedure is to enable the function, let it run for an -hour or so, then edit the configuration file using the <tt> -time1</tt> values displayed by the <tt>ntpq</tt> utility and <tt> -clockvar</tt> command. Finally, disable the calibration function to -avoid possible future disruptions due to misbehaving clocks or -drivers.</p> - + +<p>The adjustment function is an exponential average designed to improve +accuracy, so the function takes some time to converge. The recommended procedure +is to enable the function, let it run for an hour or so, then edit the configuration +file using the <tt> time1</tt> values displayed by the <tt>ntpq</tt> utility +and <tt> clockvar</tt> command. Finally, disable the calibration function +to avoid possible future disruptions due to misbehaving clocks or drivers.</p> + <h4>Performance Enhancements</h4> - -<p>In general, performance can be improved, especially when more -than one clock driver is supported, to use the prefer peer function -described in the <a href="prefer.htm">Mitigation Rules and the <tt> -prefer</tt> Keyword</a> page. The prefer peer is ordinarily -designated the remote peer or local clock driver which provides the -best quality time. All other things equal, only the prefer peer -source is used to discipline the system clock and jitter-producing -"clockhopping" between sources is avoided. This is valuable when -more than one clock driver is present and especially valuable when -the PPS clock driver (type 22) is used. Support for PPS signals is -summarized in the <a href="pps.htm">Pulse-per-second (PPS) Signal -Interfacing</a> page.</p> - -<p>Where the highest performance is required, generally better than -one millisecond, additional hardware and/or software functions may -be required. Kernel modifications for precision time are described -in the <a href="kern.htm">A Kernel Model for Precision -Timekeeping</a> page. Special line discipline and streams modules + +<p>In general, performance can be improved, especially when more than one +clock driver is supported, to use the prefer peer function described in the +<a href="prefer.htm">Mitigation Rules and the <tt> prefer</tt> Keyword</a> +page. The prefer peer is ordinarily designated the remote peer or local clock +driver which provides the best quality time. All other things equal, only +the prefer peer source is used to discipline the system clock and jitter-producing +"clockhopping" between sources is avoided. This is valuable when more than +one clock driver is present and especially valuable when the PPS clock driver +(type 22) is used. Support for PPS signals is summarized in the <a + href="pps.htm">Pulse-per-second (PPS) Signal Interfacing</a> page.</p> + +<p>Where the highest performance is required, generally better than one millisecond, +additional hardware and/or software functions may be required. Kernel modifications +for precision time are described in the <a href="kern.htm">A Kernel Model +for Precision Timekeeping</a> page. Special line discipline and streams modules for use in capturing precision timestamps are described in the <a -href="ldisc.htm">Line Disciplines and Streams Drivers</a> page.</p> - + href="ldisc.htm">Line Disciplines and Streams Drivers</a> page.</p> + <h4>Comprehensive List of Clock Drivers</h4> - -<p>Following is a list showing the type and title of each driver -currently implemented. The compile-time identifier for each is -shown in parentheses. Click on a selected type for specific -description and configuration documentation, including the clock -address, reference ID, driver ID, device name and serial line -speed, and features (line disciplines, etc.). For those drivers -without specific documentation, please contact the author listed in -the <a href="copyright.htm">Copyright Notice</a> page.</p> - -<p><a href="driver1.htm">Type 1</a> Undisciplined Local Clock -(<tt>LOCAL</tt>)<br> -<a href="driver2.htm">Type 2</a> Trak 8820 GPS Receiver -(<tt>GPS_TRAK</tt>)<br> -<a href="driver3.htm">Type 3</a> PSTI/Traconex 1020 WWV/WWVH -Receiver (<tt>WWV_PST</tt>)<br> -<a href="driver4.htm">Type 4</a> Spectracom WWVB and GPS Receivers -(<tt>WWVB_SPEC</tt>)<br> -<a href="driver5.htm">Type 5</a> TrueTime GPS/GOES/OMEGA Receivers -(<tt>TRUETIME</tt>)<br> -<a href="driver6.htm">Type 6</a> IRIG Audio Decoder -(<tt>IRIG_AUDIO</tt>)<br> -<a href="driver7.htm">Type 7</a> Radio CHU Audio -Demodulator/Decoder (<tt>CHU</tt>)<br> -<a href="driver8.htm">Type 8</a> Generic Reference Driver -(<tt>PARSE</tt>)<br> -<a href="driver9.htm">Type 9</a> Magnavox MX4200 GPS Receiver -(<tt>GPS_MX4200</tt>)<br> -<a href="driver10.htm">Type 10</a> Austron 2200A/2201A GPS -Receivers (<tt>GPS_AS2201</tt>)<br> -<a href="driver11.htm">Type 11</a> Arbiter 1088A/B GPS Receiver -(<tt>GPS_ARBITER</tt>)<br> -<a href="driver12.htm">Type 12</a> KSI/Odetics TPRO/S IRIG -Interface (<tt>IRIG_TPRO</tt>)<br> -Type 13 Leitch CSD 5300 Master Clock Controller -(<tt>ATOM_LEITCH</tt>)<br> -Type 14 EES M201 MSF Receiver (<tt>MSF_EES</tt>)<br> -<a href="driver5.htm">Type 15</a> * TrueTime generic receivers<br> -<a href="driver16">Type 16</a> Bancomm GPS/IRIG Receiver -(<tt>GPS_BANCOMM</tt>)<br> -Type 17 Datum Precision Time System (<tt>GPS_DATUM</tt>)<br> -<a href="driver18.htm">Type 18</a> NIST Modem Time Service -(<tt>ACTS_NIST</tt>)<br> -<a href="driver19.htm">Type 19</a> Heath WWV/WWVH Receiver -(<tt>WWV_HEATH</tt>)<br> -<a href="driver20.htm">Type 20</a> Generic NMEA GPS Receiver -(<tt>NMEA</tt>)<br> -Type 21 TrueTime GPS-VME Interface (<tt>GPS_VME</tt>)<br> -<a href="driver22.htm">Type 22</a> PPS Clock Discipline -(<tt>PPS</tt>)<br> -<a href="driver23.htm">Type 23</a> PTB Modem Time Service -(<tt>ACTS_PTB</tt>)<br> -<a href="driver24.htm">Type 24</a> USNO Modem Time Service -(<tt>ACTS_USNO</tt>)<br> -<a href="driver5.htm">Type 25</a> * TrueTime generic receivers<br> -<a href="driver26.htm">Type 26</a> Hewlett Packard 58503A GPS -Receiver (<tt>GPS_HP</tt>)<br> -<a href="driver27.htm">Type 27</a> Arcron MSF Receiver -(<tt>MSF_ARCRON</tt>)<br> -<a href="driver28.htm">Type 28</a> Shared Memory Driver -(<tt>SHM</tt>)<br> -<a href="driver29.htm">Type 29</a> Trimble Navigation Palisade GPS -(<tt>GPS_PALISADE</tt>)<br> -<a href="driver30.htm">Type 30</a> Motorola UT Oncore GPS -(<tt>GPS_ONCORE</tt>)<br> -Type 31 Rockwell Jupiter GPS (<tt>GPS_JUPITER</tt>)<br> -<a href="driver32.htm">Type 32</a> Chrono-log K-series WWVB -receiver (<tt>CHRONOLOG</tt>)<br> -<a href="driver33.htm">Type 33</a> Dumb Clock (<tt>DUMBCLOCK</tt>)<br> -<a href="driver34.htm">Type 34</a> Ultralink WWVB Receivers (<tt>ULINK</tt>)<br> -<a href="driver35.htm">Type 35</a> Conrad Parallel Port Radio Clock -(<tt>PCF</tt>)<br> -<a href="driver36.htm">Type 36</a> Radio WWV/H Audio -Demodulator/Decoder (<tt>WWV</tt>)<br> -<a href="driver37.htm">Type 37</a> Forum Graphic GPS Dating station -(<tt>FG</tt>)<br> -<a href="driver38.htm">Type 38</a> hopf GPS/DCF77 6021/komp for -Serial Line (<tt>HOPF_S</tt>)<br> -<a href="driver39.htm">Type 39</a> hopf GPS/DCF77 6039 for PCI-Bus -(<tt>HOPF_P</tt>)<br> -<a href="driver40.htm">Type 40</a> JJY Receivers (<tt>JJY</tt>)<br> -</p> - - -<p>* All TrueTime receivers are now supported by one driver, type -5. Types 15 and 25 will be retained only for a limited time and may -be reassigned in future.</p> - + +<p>Following is a list showing the type and title of each driver currently +implemented. The compile-time identifier for each is shown in parentheses. +Click on a selected type for specific description and configuration documentation, +including the clock address, reference ID, driver ID, device name and serial +line speed, and features (line disciplines, etc.). For those drivers without +specific documentation, please contact the author listed in the <a + href="copyright.htm">Copyright Notice</a> page.</p> + +<p><a href="driver1.htm">Type 1</a> Undisciplined Local Clock (<tt>LOCAL</tt>)<br> + <a href="driver2.htm">Type 2</a> Trak 8820 GPS Receiver (<tt>GPS_TRAK</tt>)<br> + <a href="driver3.htm">Type 3</a> PSTI/Traconex 1020 WWV/WWVH Receiver (<tt>WWV_PST</tt>)<br> + <a href="driver4.htm">Type 4</a> Spectracom WWVB and GPS Receivers (<tt>WWVB_SPEC</tt>)<br> + <a href="driver5.htm">Type 5</a> TrueTime GPS/GOES/OMEGA Receivers (<tt>TRUETIME</tt>)<br> + <a href="driver6.htm">Type 6</a> IRIG Audio Decoder (<tt>IRIG_AUDIO</tt>)<br> + <a href="driver7.htm">Type 7</a> Radio CHU Audio Demodulator/Decoder (<tt>CHU</tt>)<br> + <a href="driver8.htm">Type 8</a> Generic Reference Driver (<tt>PARSE</tt>)<br> + <a href="driver9.htm">Type 9</a> Magnavox MX4200 GPS Receiver (<tt>GPS_MX4200</tt>)<br> + <a href="driver10.htm">Type 10</a> Austron 2200A/2201A GPS Receivers (<tt>GPS_AS2201</tt>)<br> + <a href="driver11.htm">Type 11</a> Arbiter 1088A/B GPS Receiver (<tt>GPS_ARBITER</tt>)<br> + <a href="driver12.htm">Type 12</a> KSI/Odetics TPRO/S IRIG Interface (<tt>IRIG_TPRO</tt>)<br> + Type 13 Leitch CSD 5300 Master Clock Controller (<tt>ATOM_LEITCH</tt>)<br> + Type 14 EES M201 MSF Receiver (<tt>MSF_EES</tt>)<br> + <a href="driver5.htm">Type 15</a> * TrueTime generic receivers<br> + <a href="driver16">Type 16</a> Bancomm GPS/IRIG Receiver (<tt>GPS_BANCOMM</tt>)<br> + Type 17 Datum Precision Time System (<tt>GPS_DATUM</tt>)<br> + <a href="driver18.htm">Type 18</a> NIST Modem Time Service (<tt>ACTS_NIST</tt>)<br> + <a href="driver19.htm">Type 19</a> Heath WWV/WWVH Receiver (<tt>WWV_HEATH</tt>)<br> + <a href="driver20.htm">Type 20</a> Generic NMEA GPS Receiver (<tt>NMEA</tt>)<br> + Type 21 TrueTime GPS-VME Interface (<tt>GPS_VME</tt>)<br> + <a href="driver22.htm">Type 22</a> PPS Clock Discipline (<tt>PPS</tt>)<br> + <a href="driver23.htm">Type 23</a> PTB Modem Time Service (<tt>ACTS_PTB</tt>)<br> + <a href="driver24.htm">Type 24</a> USNO Modem Time Service (<tt>ACTS_USNO</tt>)<br> + <a href="driver5.htm">Type 25</a> * TrueTime generic receivers<br> + <a href="driver26.htm">Type 26</a> Hewlett Packard 58503A GPS Receiver (<tt>GPS_HP</tt>)<br> + <a href="driver27.htm">Type 27</a> Arcron MSF Receiver (<tt>MSF_ARCRON</tt>)<br> + <a href="driver28.htm">Type 28</a> Shared Memory Driver (<tt>SHM</tt>)<br> + <a href="driver29.htm">Type 29</a> Trimble Navigation Palisade GPS (<tt>GPS_PALISADE</tt>)<br> + <a href="driver30.htm">Type 30</a> Motorola UT Oncore GPS (<tt>GPS_ONCORE</tt>)<br> + Type 31 Rockwell Jupiter GPS (<tt>GPS_JUPITER</tt>)<br> + <a href="driver32.htm">Type 32</a> Chrono-log K-series WWVB receiver (<tt>CHRONOLOG</tt>)<br> + <a href="driver33.htm">Type 33</a> Dumb Clock (<tt>DUMBCLOCK</tt>)<br> + <a href="driver34.htm">Type 34</a> Ultralink WWVB Receivers (<tt>ULINK</tt>)<br> + <a href="driver35.htm">Type 35</a> Conrad Parallel Port Radio Clock (<tt>PCF</tt>)<br> + <a href="driver36.htm">Type 36</a> Radio WWV/H Audio Demodulator/Decoder +(<tt>WWV</tt>)<br> + <a href="driver37.htm">Type 37</a> Forum Graphic GPS Dating station (<tt>FG</tt>)<br> + <a href="driver38.htm">Type 38</a> hopf GPS/DCF77 6021/komp for Serial Line +(<tt>HOPF_S</tt>)<br> + <a href="driver39.htm">Type 39</a> hopf GPS/DCF77 6039 for PCI-Bus (<tt>HOPF_P</tt>)<br> + <a href="driver40.htm">Type 40</a> JJY Receivers (<tt>JJY</tt>)<br> +<a href="driver44.htm">Type 44</a> NeoClock4X DCF77 / TDF receiver<br> + </p> + +<p>* All TrueTime receivers are now supported by one driver, type 5. Types +15 and 25 will be retained only for a limited time and may be reassigned +in future.</p> + <p>Additional Information</p> - -<p><a href="prefer.htm">Mitigation Rules and the <tt>prefer</tt> -Keyword</a><br> -<a href="rdebug.htm">Debugging Hints for Reference Clock -Drivers</a><br> -<a href="kern.htm">A Kernel Model for Precision Timekeeping</a><br> -<a href="ldisc.htm">Line Disciplines and Streams Drivers</a><br> -<a href="audio.htm">Reference Clock Audio Drivers</a><br> -<a href="pps.htm">Pulse-per-second (PPS) Signal Interfacing</a><br> -<a href="howto.htm">How To Write a Reference Clock Driver</a></p> - -<hr> -<a href="index.htm"><img align="left" src="pic/home.gif" alt= -"gif"></a> - -<address><a href="mailto:mills@udel.edu">David L. Mills -<mills@udel.edu></a></address> + +<p><a href="prefer.htm">Mitigation Rules and the <tt>prefer</tt> Keyword</a><br> + <a href="rdebug.htm">Debugging Hints for Reference Clock Drivers</a><br> + <a href="kern.htm">A Kernel Model for Precision Timekeeping</a><br> + <a href="ldisc.htm">Line Disciplines and Streams Drivers</a><br> + <a href="audio.htm">Reference Clock Audio Drivers</a><br> + <a href="pps.htm">Pulse-per-second (PPS) Signal Interfacing</a><br> + <a href="howto.htm">How To Write a Reference Clock Driver</a></p> + +<hr> <a href="index.htm"><img align="left" src="pic/home.gif" alt="gif"> +</a> +<address><a href="mailto:mills@udel.edu">David L. Mills <mills@udel.edu></a></address> + <br> </body> </html> - |