<!doctype html public "-//w3c//dtd html 4.0 transitional//en"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <title>Trimble Palisade Receiver</title> </head> <body text="#000000" bgcolor="#FFFFFF" link="#0000FF" vlink="#800080" alink="#FF0000"> <h1> <font size=+2>Trimble Palisade Receiver</font> <hr></h1> <h2> <img SRC="pic/driver29.gif" NOSAVE height=100 width=420></h2> <h2> <font size=+1>Synopsis</font></h2> <table> <tr> <td> <div align=right><tt>Address: </tt></div> </td> <td><b>127.127.29.<i>u</i></b></td> </tr> <tr> <td> <div align=right><tt>Reference ID:</tt></div> </td> <td><a NAME="REFID"></a><b>GPS</b></td> </tr> <tr> <td> <div align=right><tt>Driver ID:</tt></div> </td> <td><b>GPS_PALISADE</b></td> </tr> <tr> <td> <div align=right><tt>Serial Port:</tt></div> </td> <td><b>/dev/palisade<i>u</i></b></td> </tr> <tr> <td> <div align=right><tt><font size=+1>Serial I/O:</font></tt></div> </td> <td><b>9600 baud, 8-bits, 1-stop, odd parity</b></td> </tr> </table> <h2> <font size=+1>Description</font></h2> The <b>refclock_palisade</b> driver supports <a href="http://www.trimble.com/products/ntp">Trimble Navigation's Palisade Smart Antenna GPS receiver</a>. <br>Additional software and information about the Palisade GPS is available from: <a href="http://www.trimble.com/oem/ntp">http://www.trimble.com/oem/ntp</a>. <br>Latest NTP driver source, executables and documentation is maintained at: <a href="ftp://ftp.trimble.com/pub/ntp">ftp://ftp.trimble.com/pub/ntp</a> <p>This documentation describes version 7.12 of the GPS Firmware and version 2.46 (July 15, 1999) and later, of the driver source. <br> <h2> <font size=+1>Operating System Compatibility</font></h2> The Palisade driver has been tested on the following software and hardware platforms: <br> <center><table> <tr> <td VALIGN=CENTER WIDTH="23%">Platform</td> <td VALIGN=CENTER>Operating System</td> <td>NTP Sources</td> <td>Accuracy</td> </tr> <tr> <td VALIGN=CENTER WIDTH="23%">i386 (PC) </td> <td VALIGN=CENTER>Linux</td> <td>NTP Distribution</td> <td>10 us</td> </tr> <tr> <td>i386 (PC) </td> <td>Windows NT</td> <td><a href="ftp://ftp.trimble.com/pub/ntp">ftp://ftp.trimble.com/pub/ntp</a></td> <td>1 ms</td> </tr> <tr> <td VALIGN=CENTER WIDTH="23%">SUN</td> <td VALIGN=CENTER>Solaris 2.x</td> <td>NTP Distribution</td> <td>50 us</td> </tr> <tr> <td VALIGN=CENTER WIDTH="23%">Hewlett-Packard</td> <td VALIGN=CENTER>HPUX 9, 10, 11</td> <td><a href="http://us-support.external.hp.com">http://us-support.external.hp.com</a></td> <td>50 us</td> </tr> <tr> <td>Various</td> <td>Free BSD</td> <td>NTP Distribution</td> <td>20 us</td> </tr> </table></center> <h2> <font size=+1>GPS Receiver</font></h2> The Palisade GPS receiver is an 8-channel smart antenna, housing the GPS receiver, antenna and interface in a single unit, and is designed for rooftop deployment in static timing applications. <p>Palisade generates a PPS synchronized to UTC within +/- 100 ns. The Palisade's external event input with 40 nanosecond resolution is utilized by the Palisade NTP driver for asynchronous precision time transfer. <p>No user initialization of the receiver is required. This driver is compatible with the following versions of Palisade: <br> <center><table> <tr> <td VALIGN=CENTER> <center>Version</center> </td> <td VALIGN=TOP> <center>Event Input</center> </td> <td VALIGN=CENTER> <center>Trimble Part Number</center> </td> </tr> <tr> <td VALIGN=CENTER> <center>7.02</center> </td> <td VALIGN=TOP> <center>No</center> </td> <td VALIGN=CENTER> <center>26664-00</center> </td> </tr> <tr> <td ALIGN=CENTER VALIGN=CENTER> <center>7.02E</center> </td> <td VALIGN=TOP> <center>Yes</center> </td> <td VALIGN=CENTER> <center>26664-10</center> </td> </tr> <tr> <td VALIGN=CENTER> <center>7.12</center> </td> <td VALIGN=TOP> <center>Yes</center> </td> <td VALIGN=CENTER> <center>38158-00</center> </td> </tr> </table></center> <dl> <dl>Note: When using Palisade 26664-00, you must set fudge flag2 to 1 in <b>ntp.conf</b>. See <a href="#Configuration">configuration</a>.</dl> <dl> <h3> <font size=+1>GPS <a NAME="Installation"></a>Installation</font></h3> A location with unobstructed view of the horizon is recommended. Palisade is designed to be securely mounted atop standard 3/4 inch threaded pipe. <p>The 12 conductor (dia. 10 mm) power and I/O cable must be routed from the rooftop site to the NTP server and properly strain relieved. <h3> <font size=+1>GPS <a NAME="Connection"></a>Connection</font></h3> The Palisade is equipped with dual (A & B) RS-422 serial interfaces and a differential TTL PPS output. An RS-232 / RS-422 Interface Module is supplied with the Palisade NTP Synchronization Kit. Palisade <a href="#PortA">port A</a> must be connected to the NTP host server. Maximum antenna cable length is 500 meters. See the <a href="#Pinouts">pinouts</a> table for detailed connection Information. <p>Palisade's <a href="#PortB">port B</a> provides a TSIP (Trimble Standard Interface Protocol) interface for diagnostics, configuration, and monitoring. Port B and the PPS output are not currently used by the Palisade NTP reference clock driver. <br> </dl> </dl> <h2> <font size=+1>O/S Serial Port Configuration</font></h2> The driver attempts to open the device <b><tt><a href="#REFID">/dev/palisade<i>u</i></a></tt></b> where <b><i>u</i></b> is the NTP refclock unit number as defined by the LSB of the refclock address. Valid refclock unit numbers are 0 - 3. <p>The user is expected to provide a symbolic link to an available serial port device. This is typically performed by a command such as: <blockquote><tt>ln -s /dev/ttyS0 /dev/palisade0</tt></blockquote> Windows NT does not support symbolic links to device files. COM<b>x</b>: is used by the driver, based on the refclock unit number, where unit 1 corresponds to COM<b>1</b>: and unit 3 corresponds to COM3: <br> <h2> <a NAME="Configuration"></a><font size=+1>NTP Configuration</font></h2> Palisade NTP configuration file <b><tt>"ntp.conf"</tt></b> with event polling: <br><tt>#------------------------------------------------------------------------------</tt> <br><tt># The Primary reference</tt> <br><tt>server 127.127.29.0 # Trimble Palisade GPS Refclock Unit #0</tt> <br><tt>peer terrapin.csc.ncsu.edu # internet server</tt> <br><tt># Drift file for expedient re-synchronization after downtime or reboot.</tt> <br><tt>driftfile /etc/ntp.drift</tt> <br><tt>#------------------------------------------------------------------------------</tt> <p>Configuration without event polling: <br><tt>#------------------------------------------------------------------------------</tt> <br><tt># The Primary reference</tt> <br><tt>server 127.127.29.0 # Trimble Palisade GPS (Stratum 1).</tt> <br><tt># Set packet delay</tt> <br><tt><a href="#time1">fudge 127.127.29.0 time1 0.020</a></tt> <br><tt># and set flag2 to turn off event polling.</tt> <br><tt><a href="#flag2">fudge 127.127.29.0 flag2 1</a></tt> <br><tt>#------------------------------------------------------------------------------</tt> <br> <h2> <a NAME="TimeTransfer"></a><font size=+1>Time Transfer and Polling</font></h2> Time transfer to the NTP host is performed via the Palisade's comprehensive time packet output. The time packets are output once per second, and whenever an event timestamp is requested. <p>The driver requests an event time stamp at the end of each polling interval, by pulsing the RTS (request to send) line on the serial port. The Palisade GPS responds with a time stamped event packet. <p>Time stamps are reported by the Palisade with respect to UTC time. The GPS receiver must download UTC offset information from GPS satellites. After an initial UTC download, the receiver will always start with correct UTC offset information. <br> <h2> <font size=+1>Run NTP in Debugging Mode</font></h2> The following procedure is recommended for installing and testing a Palisade NTP driver: <ol> <li> Perform initial checkout procedures. Place the GPS receiver outdoors; with clear view of the sky. Allow the receiver to obtain an UTC almanac.</li> <li> Verify presence of timing packets by observing the 1 Hz (PPS) led on the interface module. It should flash once per second.</li> <li> Connect Palisade's port A to the NTP host.</li> <li> Configure NTP and the serial I/O port on the host system.</li> <li> Initially use <tt><a href="#flag2">fudge flag2</a></tt> in <b><a href="#Configuration">ntp.conf</a>,</b> to disable event polling (see configuration).</li> <li> Run NTP in debug mode (-d -d), to observe Palisade_receive events.</li> <li> The driver reports the <a href="#TrackingStatus">tracking status of the receiver</a>. Make sure it is tracking several satellites.</li> <li> Remove fudge flag2 and restart <b>ntpd</b> in debug mode to observe palisade_receive events.</li> <li> If event polling fails, verify the <a href="#Pinouts">connections</a> and that the host hardware supports RTS control.</li> </ol> <h2> <font size=+1>Event Logging</font></h2> System and Event log entries are generated by NTP to report significant system events. Administrators should monitor the system log to observe NTP error messages. Log entries generated by the Palisade NTP reference clock driver will be of the form: <blockquote> <pre>Nov 14 16:16:21 terrapin ntpd[1127]: Palisade #0: <i>message</i></pre> </blockquote> <h2> <font size=+1>Fudge Factors</font></h2> <dl> <dt> <a NAME="time1"></a><tt><font size=+1><a href="#Configuration">time1 <i>time</i></a></font></tt></dt> <dd> Specifies the time offset calibration factor, in seconds and fraction, with default 0.0. If event capture is not used, time1 should be set to 20 milliseconds to correct serial line and operating system delays incurred in capturing time stamps from the synchronous packets.</dd> <dt> <tt><font size=+1>stratum <i>number</i></font></tt></dt> <dd> Specifies the driver stratum, in decimal from 0 to 15, with default 0.</dd> <dt> <tt><font size=+1><a href="#REFID">refid <i>string</i></a></font></tt></dt> <dd> Specifies the driver reference identifier, <b>GPS</b>.</dd> <dt> <a NAME="flag2"></a><tt><font size=+1><a href="#Configuration">flag2 0 | 1</a></font></tt></dt> <dd> When set to 1, driver does not use hardware event capture. The synchronous packet output by the receiver at the beginning of each second is time stamped by the driver. If triggering the event pulse fails, the driver falls back to this mode automatically.</dd> </dl> <h2> <font size=+1>DEFINEs</font></h2> The following constants are defined in the driver source code. These defines may be modified to improve performance or adapt to new operating systems. <br> <center><table BORDER > <tr> <td><b>Label</b></td> <td>Definition</td> <td>Default Value</td> </tr> <tr> <td>DEVICE</td> <td>The serial port device to be used by the driver</td> <td>/dev/palisade<b><i>u</i></b></td> </tr> <tr> <td>PRECISION</td> <td>Accuracy of time transfer</td> <td>1 microsecond</td> </tr> <tr> <td>CURRENT_UTC</td> <td>Valid GPS - UTC offset</td> <td>13</td> </tr> <tr> <td>SPEED232</td> <td>Host RS-232 baud rate</td> <td>B9600</td> </tr> <tr> <td>TRMB_MINPOLL </td> <td>Minimum polling interval</td> <td>5 (32 seconds)</td> </tr> <tr> <td>TRMB_MAXPOLL</td> <td>Maximum interval between polls</td> <td>7 (128 seconds)</td> </tr> </table></center> <h2> <a NAME="DataFormat"></a><font size=+1>Data Format</font></h2> Palisade port A can output two synchronous time packets. The NTP driver can use either packet for synchronization. Packets are formatted as follows: <h3> <b><font size=+0>Packet 8F-AD (Primary NTP Packet)</font></b></h3> <center><table> <tr> <td>Byte</td> <td>Item</td> <td>Type</td> <td>Meaning</td> </tr> <tr> <td>0</td> <td>Sub-Packet ID</td> <td>BYTE</td> <td>Subcode 0xAD</td> </tr> <tr> <td>1 - 2</td> <td>Event Count</td> <td>INTEGER</td> <td>External event count recorded (0 = PPS)</td> </tr> <tr> <td>3 - 10</td> <td>Fractional Second</td> <td>DOUBLE</td> <td>Time elapsed in current second (s)</td> </tr> <tr> <td>11</td> <td>Hour</td> <td>BYTE</td> <td>Hour (0 - 23)</td> </tr> <tr> <td>12</td> <td>Minute</td> <td>BYTE</td> <td>Minute (0 - 59)</td> </tr> <tr> <td>13</td> <td>Second</td> <td>BYTE</td> <td>Second (0 - 59; 60 = leap)</td> </tr> <tr> <td>14</td> <td>Day</td> <td>BYTE</td> <td>Date (1 - 31)</td> </tr> <tr> <td>15</td> <td>Month</td> <td>BYTE</td> <td>Month (1 - 12)</td> </tr> <tr> <td>16 - 17</td> <td>Year</td> <td>INTEGER</td> <td>Year (4 digit)</td> </tr> <tr> <td>18</td> <td>Receiver Status</td> <td>BYTE</td> <td>Tracking Status</td> </tr> <tr> <td>19</td> <td>UTC Flags</td> <td>BYTE</td> <td>Leap Second Flags</td> </tr> <tr> <td>20</td> <td>Reserved</td> <td>BYTE</td> <td>Contains 0xFF</td> </tr> <tr> <td>21</td> <td>Reserved</td> <td>BYTE</td> <td>Contains 0xFF</td> </tr> </table></center> <blockquote> <h4> Leap Second Flag Definition:</h4> Bit 0: (1) UTC Time is available <br>Bits 1 - 3: Undefined <br>Bit 4: (1) Leap Scheduled: Leap second pending asserted by GPS control segment. <br>Bit 5: (1) Leap Pending: set 24 hours before, until beginning of leap second. <br>Bit 6: (1) GPS Leap Warning: 6 hours before until 6 hours after leap event <br>Bit 7: (1) Leap In Progress. Only set during the leap second. <h4> <a NAME="TrackingStatus"></a>Tracking Status Flag Definitions:</h4> </blockquote> <center><table BORDER=0 CELLSPACING=0 WIDTH="712" > <tr> <td VALIGN=CENTER WIDTH="5%">Code</td> <td VALIGN=CENTER WIDTH="59%">Meaning</td> <td>Accuracy</td> <td>Receiver Mode</td> </tr> <tr> <td>0</td> <td>Receiver is Navigating</td> <td>+/- 1 us</td> <td>Self Survey</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">1</td> <td VALIGN=CENTER WIDTH="59%">Static 1 Sat. Timing Mode </td> <td>+/- 1 us</td> <td>1-D Timing</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">2</td> <td VALIGN=CENTER WIDTH="59%">Approximate Time</td> <td>20 - 50 ms</td> <td>Acquisition</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">3</td> <td VALIGN=CENTER WIDTH="59%">Startup</td> <td>N/A</td> <td>Initialization</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">4</td> <td VALIGN=CENTER WIDTH="59%">Startup</td> <td>N/A</td> <td>Initialization</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">5</td> <td VALIGN=CENTER WIDTH="59%">Dilution of Position too High </td> <td>5 ppm</td> <td>Self Survey</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">6</td> <td VALIGN=CENTER WIDTH="59%">Static 1 Sat. Timing: Sat. not usable</td> <td>5 ppm</td> <td>1-D Timing</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">7</td> <td VALIGN=CENTER WIDTH="59%">No Satellites Usable</td> <td>N/A</td> <td>Self Survey</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">8</td> <td VALIGN=CENTER WIDTH="59%">Only 1 Satellite Usable</td> <td>20 - 50 ms</td> <td>Self Survey</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">9</td> <td VALIGN=CENTER WIDTH="59%">Only 2 Satellite Usable</td> <td>20 - 50 ms</td> <td>Self Survey</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">10</td> <td VALIGN=CENTER WIDTH="59%">Only 3 Satellites Usable</td> <td>20 - 50 ms</td> <td>Self Survey</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">11</td> <td VALIGN=CENTER WIDTH="59%">Invalid Solution</td> <td>N/A</td> <td>Error</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">12</td> <td VALIGN=CENTER WIDTH="59%">Differential Corrections </td> <td>N/A</td> <td>N/A</td> </tr> <tr> <td VALIGN=CENTER WIDTH="5%">13</td> <td VALIGN=CENTER WIDTH="59%">Overdetermined Fixes</td> <td>+/- 100 ns</td> <td>Timing Steady State</td> </tr> </table></center> <h3> <b><font size=+0>Packet 8F-0B (Comprehensive Timing Packet)</font></b></h3> <center><table BORDER=0 CELLSPACING=0 > <tr> <td VALIGN=CENTER WIDTH="9%">Byte</td> <td VALIGN=CENTER WIDTH="27%">Item</td> <td VALIGN=CENTER WIDTH="16%">Type</td> <td VALIGN=CENTER WIDTH="48%">Meaning</td> </tr> <tr> <td VALIGN=CENTER WIDTH="9%">0</td> <td VALIGN=CENTER WIDTH="27%">Sub-Packet ID</td> <td VALIGN=CENTER WIDTH="16%">BYTE</td> <td VALIGN=CENTER WIDTH="48%">Subcode 0x0B</td> </tr> <tr> <td VALIGN=TOP WIDTH="9%">1 - 2</td> <td VALIGN=TOP WIDTH="27%">Event Count</td> <td VALIGN=TOP WIDTH="16%">INTEGER</td> <td VALIGN=TOP WIDTH="48%">External event count recorded (0 = PPS)</td> </tr> <tr> <td VALIGN=TOP WIDTH="9%">3 - 10</td> <td VALIGN=TOP WIDTH="27%">UTC / GPS TOW</td> <td VALIGN=TOP WIDTH="16%">DOUBLE</td> <td VALIGN=TOP WIDTH="48%">UTC / GPS time of week (seconds)</td> </tr> <tr> <td VALIGN=CENTER WIDTH="9%">11</td> <td VALIGN=CENTER WIDTH="27%">Date</td> <td VALIGN=CENTER WIDTH="16%">BYTE</td> <td VALIGN=CENTER WIDTH="48%">Day of Month</td> </tr> <tr> <td VALIGN=CENTER WIDTH="9%">12</td> <td VALIGN=CENTER WIDTH="27%">Month</td> <td VALIGN=CENTER WIDTH="16%">BYTE</td> <td VALIGN=CENTER WIDTH="48%">Month of Event</td> </tr> <tr> <td VALIGN=CENTER WIDTH="9%">13 - 14</td> <td VALIGN=CENTER WIDTH="27%">Year</td> <td VALIGN=CENTER WIDTH="16%">INT</td> <td VALIGN=CENTER WIDTH="48%">Year of event</td> </tr> <tr> <td VALIGN=TOP WIDTH="9%">15</td> <td VALIGN=TOP WIDTH="27%">Receiver Mode</td> <td VALIGN=TOP WIDTH="16%">BYTE</td> <td VALIGN=TOP WIDTH="48%">Receiver operating dimensions: <br>0: Horizontal (2D) <br>1: Full Position (3D) <br>2: Single Satellite (0D) <br>3: Automatic (2D / 3D) <br>4: DGPS reference <br>5: Clock hold (2D) <br>6: Over determined Clock</td> </tr> <tr> <td VALIGN=CENTER WIDTH="9%">15 - 17</td> <td VALIGN=CENTER WIDTH="27%">UTC Offset</td> <td VALIGN=CENTER WIDTH="16%">INTEGER</td> <td VALIGN=CENTER WIDTH="48%">UTC Offset value (seconds)</td> </tr> <tr> <td VALIGN=CENTER WIDTH="9%">18 - 25</td> <td VALIGN=CENTER WIDTH="27%">Oscillator Bias</td> <td VALIGN=CENTER WIDTH="16%">DOUBLE</td> <td VALIGN=CENTER WIDTH="48%">Oscillator BIAS (meters)</td> </tr> <tr> <td VALIGN=TOP WIDTH="9%">26 - 33</td> <td VALIGN=TOP WIDTH="27%">Oscillator Drift Rate</td> <td VALIGN=TOP WIDTH="16%">DOUBLE</td> <td VALIGN=TOP WIDTH="48%">Oscillator Drift (meters / second)</td> </tr> <tr> <td VALIGN=CENTER WIDTH="9%">34 - 37</td> <td VALIGN=CENTER WIDTH="27%">Bias Uncertainty</td> <td VALIGN=CENTER WIDTH="16%">SINGLE</td> <td VALIGN=CENTER WIDTH="48%">Oscillator bias uncertainty (meters)</td> </tr> <tr> <td VALIGN=CENTER WIDTH="9%">38 - 41</td> <td VALIGN=CENTER WIDTH="27%">Drift Uncertainty</td> <td VALIGN=CENTER WIDTH="16%">SINGLE</td> <td VALIGN=CENTER WIDTH="48%">Oscillator bias rate uncertainty (m / sec)</td> </tr> <tr> <td VALIGN=CENTER WIDTH="9%">42 - 49</td> <td VALIGN=CENTER WIDTH="27%">Latitude</td> <td VALIGN=CENTER WIDTH="16%">DOUBLE</td> <td VALIGN=CENTER WIDTH="48%">Latitude in radians</td> </tr> <tr> <td VALIGN=CENTER WIDTH="9%">50 - 57</td> <td VALIGN=CENTER WIDTH="27%">Longitude</td> <td VALIGN=CENTER WIDTH="16%">DOUBLE</td> <td VALIGN=CENTER WIDTH="48%">Longitude in radians</td> </tr> <tr> <td VALIGN=CENTER WIDTH="9%">58 - 65</td> <td VALIGN=CENTER WIDTH="27%">Altitude</td> <td VALIGN=CENTER WIDTH="16%">DOUBLE</td> <td VALIGN=CENTER WIDTH="48%">Altitude above mean sea level, in meters</td> </tr> <tr> <td VALIGN=CENTER WIDTH="9%">66 - 73</td> <td VALIGN=CENTER WIDTH="27%">Satellite ID</td> <td VALIGN=CENTER WIDTH="16%">BYTE</td> <td VALIGN=CENTER WIDTH="48%">SV Id No. of tracked satellites</td> </tr> </table></center> <h2> <a NAME="Pinouts"></a><font size=+1>Pinouts</font></h2> <a href="#Connection">The following connections are required when connecting Palisade with a host:</a> <br> <br> <center><table> <tr> <td><u>Description</u></td> <td><b>Host</b></td> <td></td> <td></td> <td><b>Palisade </b></td> <td></td> <td></td> </tr> <tr> <td><a NAME="PortA"></a><b>Port A</b></td> <td><u>DB-9</u></td> <td><u>DB-25</u></td> <td></td> <td><u>RS-232</u></td> <td><u>RS-422</u></td> <td><u>Palisade Pin</u></td> </tr> <tr> <td>Receive Data </td> <td>2</td> <td>3</td> <td><--></td> <td>Green</td> <td>Green / Blue</td> <td>8 (T-) & 10 (T+)</td> </tr> <tr> <td>Request to Send</td> <td>7</td> <td>4</td> <td><--></td> <td>Gray</td> <td>Gray / White</td> <td>6 (R-) & 7 (R+)</td> </tr> <tr> <td>Signal Ground</td> <td>5</td> <td>7</td> <td><--></td> <td>Black</td> <td>Black</td> <td>9 (GND)</td> </tr> <tr> <td></td> <td></td> <td></td> <td></td> <td></td> <td></td> <td></td> </tr> <tr> <td><a NAME="PortB"></a><b>Port B</b></td> <td></td> <td></td> <td></td> <td></td> <td></td> <td></td> </tr> <tr> <td>Receive Data </td> <td>2</td> <td>3</td> <td><--></td> <td>Brown</td> <td>Brown / Yellow</td> <td>4 (T-) & 5 (T+)</td> </tr> <tr> <td>Transmit Data</td> <td>3</td> <td>2</td> <td><--></td> <td>Violet</td> <td>Orange/ Violet</td> <td>2 (R-) & 3 (R+)</td> </tr> <tr> <td>Signal Ground</td> <td>5</td> <td>7</td> <td><--></td> <td>Black</td> <td>Black</td> <td>9 (GND)</td> </tr> </table></center> <blockquote>Note: If driving the RS-422 inputs on the Palisade single ended, i.e. using the Green and Gray connections only, does not work on all serial ports. Use of the Palisade NTP Synchronization Interface Module is recommended.</blockquote> <blockquote>The 12 pin connector pinout definition: <br>Face the round 12 pin connector at the end of the cable, with the notch turned upwards. <br>Pin 1 is to the left of the notch. Pins 2 - 8 wrap around the bottom, counterclockwise to pin 9 on the right of the notch. Pin 10 is just below the notch. Pins 10 (top), 11 (bottom left) and 12 (bottom right) form a triangle in the center of the connector.</blockquote> <blockquote><a NAME="SIM"></a>Pinouts for the Palisade NTP host adapter (Trimble PN 37070) DB-25 M connector are as follows:</blockquote> <center><table BORDER=0 CELLSPACING=0 WIDTH="682" > <tr> <td VALIGN=CENTER WIDTH="12%">DB-25M</td> <td VALIGN=CENTER WIDTH="31%">Conductor </td> <td VALIGN=CENTER WIDTH="16%">Palisade</td> <td VALIGN=CENTER WIDTH="41%">Description</td> </tr> <tr> <td VALIGN=CENTER WIDTH="12%">1 </td> <td VALIGN=CENTER WIDTH="31%">Red</td> <td VALIGN=CENTER WIDTH="16%">1</td> <td VALIGN=CENTER WIDTH="41%">Power</td> </tr> <tr> <td VALIGN=CENTER WIDTH="12%">7 </td> <td VALIGN=CENTER WIDTH="31%">Black</td> <td VALIGN=CENTER WIDTH="16%">9</td> <td VALIGN=CENTER WIDTH="41%">Ground</td> </tr> <tr> <td VALIGN=CENTER WIDTH="12%">9</td> <td VALIGN=CENTER WIDTH="31%">Black/White</td> <td VALIGN=CENTER WIDTH="16%">12</td> <td VALIGN=CENTER WIDTH="41%">PPS -</td> </tr> <tr> <td VALIGN=CENTER WIDTH="12%">10 </td> <td VALIGN=CENTER WIDTH="31%">Green</td> <td VALIGN=CENTER WIDTH="16%">8</td> <td VALIGN=CENTER WIDTH="41%">Transmit Port A (T-)</td> </tr> <tr> <td VALIGN=CENTER WIDTH="12%">11 </td> <td VALIGN=CENTER WIDTH="31%">Brown</td> <td VALIGN=CENTER WIDTH="16%">4</td> <td VALIGN=CENTER WIDTH="41%">Transmit Port B (T-)</td> </tr> <tr> <td VALIGN=CENTER WIDTH="12%">12 </td> <td VALIGN=CENTER WIDTH="31%">Gray</td> <td VALIGN=CENTER WIDTH="16%">7</td> <td VALIGN=CENTER WIDTH="41%">Receive Port A (R+)</td> </tr> <tr> <td VALIGN=CENTER WIDTH="12%">13</td> <td VALIGN=CENTER WIDTH="31%">Orange</td> <td VALIGN=CENTER WIDTH="16%">3</td> <td VALIGN=CENTER WIDTH="41%">Receive Port B (R+)</td> </tr> <tr> <td VALIGN=CENTER WIDTH="12%">21</td> <td VALIGN=CENTER WIDTH="31%">Orange/White</td> <td VALIGN=CENTER WIDTH="16%">11</td> <td VALIGN=CENTER WIDTH="41%">PPS +</td> </tr> <tr> <td VALIGN=CENTER WIDTH="12%">22</td> <td VALIGN=CENTER WIDTH="31%">Blue</td> <td VALIGN=CENTER WIDTH="16%">10</td> <td VALIGN=CENTER WIDTH="41%">Transmit Port A (T+)</td> </tr> <tr> <td VALIGN=CENTER WIDTH="12%">23</td> <td VALIGN=CENTER WIDTH="31%">Yellow</td> <td VALIGN=CENTER WIDTH="16%">5</td> <td VALIGN=CENTER WIDTH="41%">Transmit Port B (T+)</td> </tr> <tr> <td VALIGN=CENTER WIDTH="12%">24</td> <td VALIGN=CENTER WIDTH="31%">White</td> <td VALIGN=CENTER WIDTH="16%">6</td> <td VALIGN=CENTER WIDTH="41%">Receive Port A (R-)</td> </tr> <tr> <td VALIGN=CENTER WIDTH="12%">25</td> <td VALIGN=CENTER WIDTH="31%">Violet</td> <td VALIGN=CENTER WIDTH="16%">2</td> <td VALIGN=CENTER WIDTH="41%">Receive Port B (R-)</td> </tr> </table></center> <p> <hr> <p>Questions or Comments: <br><a href="mailto:sven_dietrich@trimble.com">Sven Dietrich</a> <br><a href="http://www.trimble.com/">Trimble Navigation Ltd.</a> <p>(last updated July 29, 1999) <br> </body> </html>