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October 2, 2001

VP Oncore Command Reference

This document contains command and reply messages for the 6 channel PVT-6 and Basic

Oncore and the 6 and 8 channel VP Oncore as supported by Synergy Systems, LLC beginning in

1992. It has been independently compiled and audited by Synergy Systems, LLC and checked

against Motorola’s Technical Reference Manual TRM0001 version 7.0 dated May 1996 for the VP

Oncore series of OEM GPS receivers. For completeness, portions of this document include

original text from TRM0001, reproduced here with Motorola’s permission, and annotated with

notes and clarifications by Synergy Systems, LLC. This document is made available in

hyperlinked PDF to provide easy access to command and output message details by electronic

means.

Although Synergy Systems, LLC has been extremely diligent in compiling and listing the message

details and checking the final document, neither Motorola nor Synergy Systems, LLC can

guarantee that this document is either a complete reference and/or is free of errors. By

downloading and/or opening this command reference file, accessing any of the pages and/or

using any of the command/reply messages as listed, the user agrees to accept sole responsibility

for those actions and holds harmless both Motorola and Synergy Systems, LLC of any and all

liability whatsoever. Further, information in this document is subject to change without notice and

does not represent a commitment on the part of either Motorola nor Synergy Systems, LLC.

For questions or comments related to this document, please contact Synergy Systems, LLC

Technical Support via the Synergy Systems, LLC web site http://www.synergy-gps.com

, by e-mail

to tech@synergy-gps.com

or the numbers listed below.

For configuration assistance, order placement and technical support call:

P.O. Box 262250 · San Diego, CA 92196

Phone: (858) 566-0666 · Fax: (858) 566-0768

Email: Info@synergy-gps.com

Prices and/or specifications subject to change without notice.

Summary of content (147 pages)

PAGE 1
October 2, 2001 VP Oncore Command Reference This document contains command and reply messages for the 6 channel PVT-6 and Basic Oncore and the 6 and 8 channel VP Oncore as supported by Synergy Systems, LLC beginning in 1992. It has been independently compiled and audited by Synergy Systems, LLC and checked against Motorola’s Technical Reference Manual TRM0001 version 7.0 dated May 1996 for the VP Oncore series of OEM GPS receivers.
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VP ONCORE COMMAND REFERENCE WHAT EXACTLY IS A VP? I fully admit to being rather cavalier in my definition of a “VP”. This command reference is usable for early packaged Oncore receivers such as the “PVT-6”, 6 and 8 channel “Basic” Oncores, and finally the 6 and 8 channel board level product “VPs”. The common thread is that they all respond to the commands shown here (or some subset, depending on age and firmware revision.
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VP ONCORE COMMAND REFERENCE COMMAND INDEX Function Time Ephemeris Time Setup Time DOP Position Thresholds Position Receiver Position Satellite Satellite Satellite DOP Differential DOP DOP Satellite Almanac Setup Setup Setup Setup Setup Setup Setup Setup Time Time 1PPS 1PPS Position Satellite DOP Almanac Almanac Ephemeris Range Data 3 Description Time of Day Ephemeris Hold Option GMT Correction Application Type Select Date 2D to 0D HDOP Threshold Latitude Correction Thresholds Longitude Output Align Height
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VP ONCORE COMMAND REFERENCE DGPS Ephemeris Setup Position Broadcast TRAIM Receiver Almanac Satellite DGPS Receiver Receiver Format Receiver Position DOP Range Data Position TRAIM Receiver Satellite 4 Pseudorange Correction Output Ephemeris Data Output Message Leap Second Pending Status 6 Channel Position/Status/Data Extension Satellite Broadcast Data Message 6 Channel TRAIM Setup/Status 6 Channel Self Test Almanac Data Input 6 Channel Alert Planning Message Pseudorange Correction Input Set-to-Defaults Pos
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VP ONCORE COMMAND REFERENCE Back to Index TIME OF DAY (@@Aa) This input command changes the current time in the VP’s Real Time Clock (RTC) to the time specified in the command. The GMT correction (@@Ab command) and the UTC/GPS Time Mode selection (@@Aw command) should be specified before the Time of Day is set. The time in the GPS receiver will be correct if the internal RTC has been powered.
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VP ONCORE COMMAND REFERENCE TIME OF DAY (@@Aa) Motorola Binary Format Input Command • Request Current Time of Day: @@AaxxxC xxx - 3 out of range bytes C - checksum Message length: 10 bytes • $ffffff Change Current Time of Day: @@AahmsC h - hours m - minutes s - seconds C - checksum Message length: 10 bytes Response Message • 0 .. 23 0 .. 59 0 .. 59 To either command: @@AahmsC h - hours m - minutes s - seconds C - checksum Message length: 10 bytes 6 0 .. 23 0 .. 59 0 ..
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VP ONCORE COMMAND REFERENCE Back to Index EPHEMERIS HOLD OPTION (@@AA) In normal operation the GPS receiver automatically acquires and uses the latest satellite ephemerides from the GPS satellites. When the GPS receiver detects a new ephemeris data set, it collects the new data and immediately begins using the new data. If the user enables the Ephemeris Hold Option the GPS receiver holds the current ephemerides in memory and will not collect new ephemerides from the GPS satellites.
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VP ONCORE COMMAND REFERENCE EPHEMERIS HOLD OPTION (@@AA) Motorola Binary Format Input Command • Request Current Ephemeris Hold Mode: @@AAxC x - $ff (one byte, hex if) C - checksum Message Length: 8 bytes • Change Current Ephemeris Hold Mode: @@AAmC m - mode 0 - Disabled 1 - Enabled C - checksum Message Length: 8 bytes Response Message • (to either command): @@AAmC m - mode 0 - Disabled 1 - Enabled C - checksum Message Length: 8 bytes 8 Synergy Systems, LLC 05OCT01
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VP ONCORE COMMAND REFERENCE Back to Index GMT CORRECTION (@@Ab) This command changes the offset between GMT and local time. The VP receiver computes local time from GMT and the offset using the following equation: Local Time = GMT + GMT Offset. The minutes offset is provided for those locations in the world that do not use an even offset of hours between GMT and local time.
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VP ONCORE COMMAND REFERENCE GMT CORRECTION (@@Ab) Motorola Binary Format Input Command Query Current GMT Offset: @@AbxxxC xxx - $ffffff (three bytes, all hex $ff) C – checksum Message length: 10 bytes Change current GMT Offset: @@AbshmC s - sign 00 = positive ff = negative 0 .. 23 0 .. 59 h - hours m - minutes C - checksum Message length: 10 bytes Response Message (To either command): @@AbshmC s - sign 00 = positive ff = negative 0 .. 23 0 ..
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VP ONCORE COMMAND REFERENCE Back to Index APPLICATION TYPE SELECT (@@AB) This option is used to manually change the receiver application type. Setting this parameter allows the user to select optimized search and reacquisition strategies for different receiver applications. Note the initial satellite search time is the time the receiver spends searching for the assumed visible satellites (based on the almanac and initial receiver position).
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VP ONCORE COMMAND REFERENCE APPLICATION TYPE SELECT (@@AB) Motorola Binary Format Input Command • Request Current Application Type: @@ABxC x - $ff (one byte, hex ff) C - checksum Message Length: 8 bytes • Change Current Application Type: @@ABtC t - application type 0 - Air 1 - Handheld 2 - Land 3 - Marine 4 - Static C - checksum Message Length: 8 bytes Response Message • (to either command): @@ABtC t - application type 0 - Air 1 - Handheld 2 - Land 3 - Marine 4 - Static
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VP ONCORE COMMAND REFERENCE Back to Index DATE COMMAND (@@Ac) This input command changes the current date in the GPS receiver real-time clock (RTC) to the date specified in the command. The GMT Correction should be set using the @@Ab Command before the Date is set. The date in the GPS receiver will normally be correct if the internal RTC has been powered. It is not necessary for the user to enter the current date if the RTC power is removed, however the TTFF will be reduced if the date is initialized.
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VP ONCORE COMMAND REFERENCE DATE (@@Ac) Motorola Binary Format Input Command • Request Current Date: @@AcxxxxC xxxx - 4 out of range bytes C - checksum Message length: 11 bytes • $ffffffff Change current Date: @@AcmdyyC m - month d - day yy - year C - checksum Message length: 11 bytes Response Message • 1 .. 12 1 .. 31 1980 .. 2077 To either command: @@AcmdyyC m – month d - day yy - year C - checksum Message length: 11 bytes 14 Synergy Systems, LLC 05OCT01 1 .. 12 1 ..
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VP ONCORE COMMAND REFERENCE Back to Index 2-D TO O-D HDOP THRESHOLD (@@AC) There are periods in the satellite pass where the two-dimensional (2-D) dilution of precision (HDOP) grows very large, and the position is too inaccurate for use. This command allows the user to set the DOP threshold above which the GPS receiver will quit 2-D positioning. Range: Default Value: Resolution: 15 1.0 to 99.9 12.0 0.
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VP ONCORE COMMAND REFERENCE 2-D TO O-D HDOP THRESHOLD (@@AC) Motorola Binary Format Input Command • Request current 2-D to 0-D HDOP threshold: @@ACttC xx - $ffff (two bytes, all hex ff) C – checksum Message Length: 9 bytes • Change Current 2-D to 0-D HDOP threshold: @@ACttC tt - 2-D to 0-D threshold 10 .. 999 (0.1 resolution) (1.0 .. 99.9) C - checksum Message Length: 9 bytes Response Message • (to either command): @@ACttC tt - 2-D to 0-D threshold 10 .. 999 (0.
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VP ONCORE COMMAND REFERENCE Back to Index LATITUDE (@@Ad) Three parameters (latitude, longitude, and height) are used to establish the initial position of the VP receiver. The initial position estimate provides the VP with a starting point to begin the satellite acquisition process. It is not necessary for the user to initialize the coordinates with a position estimate, however the TTFF will be minimized by providing an estimate that is close (within one degree is sufficient) to the user's position.
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VP ONCORE COMMAND REFERENCE LATITUDE (@@Ad) Motorola Binary Format In pu t Co mma nd • Request Current Latitude: @@AdxxxxC xxxx - 4 out of range hex bytes C – checksum Message length: 11 bytes • $99999999 Change current Latitude: @@AdddddC dddd - latitude in mas -324,000,000 .. 324,000,000 (-90º to 90º) C - checksum Message length: 11 bytes Response Message • (to either command) @@AdddddC dddd - latitude in mas -324,000,000 ..
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VP ONCORE COMMAND REFERENCE Back to Index CORRECTION THRESHOLDS (@@AD) This command allows the control of two timer thresholds that affect the following: • • the "smoothness" of the position fix (FlX_THR), and the "smoothness" of the differential correction output (OUT_THR). The Motorola VP Oncore GPS receiver filters the noisy raw code phase measurements with the very smooth carrier phase measurements.
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VP ONCORE COMMAND REFERENCE CORRECTION THRESHOLDS (@@AD) Motorola Binary Format Input Command • Request Correction Thresholds: @@ADxxC xx - $ffff (two bytes, all hex ff) C - checksum Message Length: 9 bytes • Change Correction Thresholds: @@ADfdC f - FIX_THR d -OUT_THR C – checksum Message Length: 9 bytes Message Response • 0 .. 127 seconds 0 .. 127 seconds (to either command): @@ADfdC f - FIX_THR d - OUT_THR C - checksum Message Length: 9 bytes 20 0 ..127 seconds 0 ..
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VP ONCORE COMMAND REFERENCE Back to Index LONGITUDE (@@Ae) Longitude is measured in degrees east (+) or degrees west (-) of the Greenwich Meridian. The default datum for the longitude is WGS-84, however this may be changed by the user with the Datum Select (@@Ao command.) This input command sets the initial longitude coordinate only if the GPS receiver is not yet computing a position fix, or is used to replace the current longitude with a new input longitude while in the Position Fix mode.
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VP ONCORE COMMAND REFERENCE LONGITUDE (@@Ae) Motorola Binary Format Input Command • Request Current Longitude: @@AexxxxC xxxx - 4 out of range hex bytes C - checksum Message length: 11 bytes • $99999999 Change current Longitude: @@AeddddC dddd - longitude in mas -648,000,000 .. 648,000,000 (-180º to 180º) C - checksum Message length: 11 bytes Response Message • (to either command) @@AeddddC dddd - longitude in mas -648,000,000 ..
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VP ONCORE COMMAND REFERENCE Back to Index OUTPUT ALIGN (@@AE) This command, when enabled, will align all receiver periodic outputs with the top of the minute. The periodic output rates which can be aligned are 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, and 60 seconds.
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VP ONCORE COMMAND REFERENCE OUTPUT ALIGN (@@AE) Motorola Binary Format Input Command • Request current Output Alignment Mode: @@AExC x - $ff (one byte, hex ff) C - checksum Message Length: 8 bytes • Change Output Alignment @@AEmC m – mode 0 - Disabled 1 - Enabled C - checksum Message Length: 8 bytes Response Message •(to either command) @@AEmC m - mode C - checksum Message Length: 8 bytes 24 Synergy Systems, LLC 05OCT01 0 - Disabled 1 - Enabled
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VP ONCORE COMMAND REFERENCE Back to Index HEIGHT (@@Af) This input command sets the initial height coordinate only if the VP receiver is not yet computing a position fix, or is used to replace the current height with a new input height while in the Position Fix mode. The user can enter the height referred to either of the two following references: • • GPS (WGS-84) Ellipsoid Height Mean Sea Level (MSL) Range: Default value: Resolution: 25 - 1,000,00 .. 18,000.00 m 0.00 meters 0.
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VP ONCORE COMMAND REFERENCE HEIGHT (@@Af) Motorola Binary Format Input Command • Request Current Height: @@AfxxxxxC xxxx - 5 out of range hex bytes C - checksum Message length: 12 bytes • $9999999999 Change current Height: @@AfhhhhtC hhhh - height in cm t - height type -100,000 .. 1,800,000 (-1,000.00 .. 18,000.
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VP ONCORE COMMAND REFERENCE Back to Index SATELLITE MASK ANGLE (@@Ag) The VP will attempt to track satellites for which the elevation angle is greater than the satellite mask angle. This parameter allows the user to control the elevation angle that was used for this decision.
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VP ONCORE COMMAND REFERENCE SATELLITE MASK ANGLE (@@Ag) Motorola Binary Format Input Command • Request current Mask Angle: @@AgxC x - $ff (one byte, hex ff) C - checksum Message length: 8 bytes • Change current Mask Angle: @@AgdC d - degrees C - checksum Message length: 8 bytes Response Message • 0 .. 89 (to either command) @@AgdC d - degrees C - checksum Message length: 8 bytes 28 0 ..
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VP ONCORE COMMAND REFERENCE Back to Index SATELLITE SELECT OPTIONS (@@Ah) This command sets the Satellite Select option to either automatic, manual, or highest-in-the-sky satellite selection. With the "automatic" option enabled, the Motorola VP GPS receiver automatically selects the set of satellites to track with the best geometry (selection criteria optimized for the selected xDOP type using the @@Aj command), the xDOP hysteresis parameter (@@Ak command), and position fix type (@@Ar command).
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VP ONCORE COMMAND REFERENCE SATELLITE SELECT OPTIONS (@@Ah) Motorola Binary Format Input Command • Query current Satellite Select Mode: @@AhxC x = $ff (one byte, hex ff) C - checksum Message Length: 8 bytes • Change Satellite Select Mode: @@AhoC o – option 0 – Automatic Best Geometry 1 – Manual 2 - Automatic Highest-In-Sky C - checksum Message Length: 8 bytes Response Message • (to either command) @@AhoC o - option 0 – Automatic Best Geometry 1 - Manual 2 - Automatic Hig
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VP ONCORE COMMAND REFERENCE Back to Index MANUAL SATELLITE SELECT (@@Ai) This option is used to manually change the satellites tracked by the Motorola VP GPS receiver. This input command is used only when the Manual Satellite Select option (Mode 1) has been enabled by the user with the Satellite Select Option (@@Ah command.) The input command has no effect if either the Automatic or Highest-inthe-Sky Satellite Select options have been enabled.
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VP ONCORE COMMAND REFERENCE SATELLITE SELECT (@@Ai) Motorola Binary Format Input Command • Query Current Satellite Assignment on Channel: @@AicxC c - channel number x - $ff (one byte, hex ff) C - checksum Message Length: 9 bytes • 1 .. 8 Change Satellite Assignment on Channel: @@AicsC c - channel number s - sat ID per channel 1 .. 8 0 .. 37 0 = Disable Channel 1 ..
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VP ONCORE COMMAND REFERENCE Back to Index xDOP TYPE (@@Aj) The xDOP Type parameter specifies which DOP type to use for satellite selection criteria.
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VP ONCORE COMMAND REFERENCE xDOP TYPE (@@Aj) Motorola Binary Format Input Command • Query Current xDOP Type: @@AjxC x - $ff (one byte, hex ff) C - checksum Message Length: 8 bytes • Change xDOP Type: @@AjdC d - DOP Type 0 - GDOP 1 - PDOP 2 - HDOP 3 - VDOP 4 - TDOP C - checksum Message Length: 8 bytes Response Message • (to either command) @@AjdC d - DOP Type 0 - GDOP 1 - PDOP 2 - HDOP 3 - VDOP 4- TDOP C - checksum Message Length: 8 bytes 34 Synergy Systems, LLC 05OCT0
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VP ONCORE COMMAND REFERENCE Back to Index DIFFERENTIAL TIME-OUT SELECT (@@AJ) The differential time-out select message allows the user to determine how long the receiver will stay in differential mode in the absence of valid updated corrections. The GPS receiver will stay in differential mode as long as it has a current and valid differential correction message. The user should note that excessive differential correction latencies could lead to significant error growth.
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VP ONCORE COMMAND REFERENCE DIFFERENTIAL TIME-OUT SELECT (@@AJ) Motorola Binary Format Input Command • Request current Differential Time-Out: @@AJxC x - $ff (one byte, hex ff) C - checksum Message Length: 8 bytes • Change differential time-out: @@AJsC s - seconds C - checksum Message Length: 8 bytes Response Message • 5 .. 180 (to either command): @@AJsC s - seconds C - checksum Message Length: 8 bytes 36 Synergy Systems, LLC 05OCT01 5 ..
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VP ONCORE COMMAND REFERENCE Back to Index xDOP HYSTERESIS (@@Ak) Setting this parameter allows the user to change the criteria by which the Motorola VP GPS receiver selects satellites. The VP evaluates the geometry for all satellites in view every few seconds.
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VP ONCORE COMMAND REFERENCE xDOP HYSTERESIS (@@Ak) Motorola Binary Format Input Command • Query Current xDOP Hysteresis: @@AkxxC xx - $ffff (two bytes, all hex ff) C - checksum Message Length: 9 bytes • Change xDOP Hysteresis: @@AkxxC xx - xDOP Hysteresis 0.1 resolution C - checksum Message Length: 9 bytes Response Message • 0 .. 999 (0.0 .. 99.9) (to either command): @@AkxxC xx - xDOP hysteresis 0.1 resolution C - checksum Message Length: 9 bytes 38 0 .. 999 (0.0.. 99.
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VP ONCORE COMMAND REFERENCE Back to Index 3-D TO 2-D xDOP THRESHOLD (@@Al) There may be periods during the day where the 3-dimensional (3-D) dilution of precision (PDOP and GDOP) grows very large, but the 2-D HDOP stays relatively small. This command allows the user to set the DOP threshold above which the GPS receiver will switch from 3-D positioning to altitude-hold at the current height.
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VP ONCORE COMMAND REFERENCE 3-D TO 2-D xDOP THRESHOLD (@@Al) Motorola Binary Format Input Command • Query Current 3-D to 2-D DOP threshold: @@AlxxC (Note: The second character is a lowercase "L" not the number "1") xx - $ffff (two bytes, both hex ff) C - checksum Message Length: 9 bytes • Change Current 3-D to 2-D DOP threshold: @@AlxxC xx - threshold (0.1 resolution) C - checksum Message Length: 9 bytes Response Message • 10 .. 999 (1.0 .. 99.
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VP ONCORE COMMAND REFERENCE Back to Index SATELLITE IGNORE LIST (@@Am) It is useful to have the flexibility to delete particular satellite identifications (IDs) from the selection process. The Motorola VP receiver includes, in its list of satellites to track, all satellites that are healthy and in the almanac. The user can elect to ignore particular satellites in the almanac by issuing an Ignore Satellite Command.
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VP ONCORE COMMAND REFERENCE SATELLITE IGNORE LIST (@@Am) Motorola Binary Format Input Command • Send Current Satellite Ignore List: @@AmxxxxxC xxxxx - $ff00000000 (five bytes, hex ff00000000) C - checksum Message Length: 12 bytes • Change Satellite ignore List: @@AmkssssC k - 00 fixed binary constant ssss - 32 bit binary field Each bit represents one SVID (MSB = SVID 32, LSB = SVID 1) 1 - Ignore 0 - Include C - checksum Message Length: 12 bytes Response Message •(to either command) @
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VP ONCORE COMMAND REFERENCE Back to Index ALMANAC UPDATE OPTION (@@An) The user has the flexibility of allowing or disallowing the GPS receiver to automatically update its internal almanac when a new one is downloaded from the GPS satellites. With the automatic almanac update enabled, the GPS receiver will continuously gather the satellite-transmitted almanac from any of the active channels and compare the new almanac to the old one stored in its nonvolatile memory.
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VP ONCORE COMMAND REFERENCE ALMANAC UPDATE OPTION (@@An) Motorola Binary Format Input Command • Query Current Almanac Update Mode: @@AnxC x - $ff (one byte, hex ff) C - checksum Message Length: 8 bytes • Change Almanac Update Mode: @@AnmC m – mode 1 – Update 0 – No Update C - checksum Message Length: 8 bytes Response Message • (to either command): @@AnmC m - mode 1 - Update 0- No Update C - checksum Message Length: 8 bytes 44 Synergy Systems, LLC 05OCT01
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VP ONCORE COMMAND REFERENCE Back to Index DATUM SELECT (@@Ao) The VP receiver has 49 predefined datums in its internal memory and two user definable datums. All datums are referenced by an ID number. The predefined datums are numbered 1 through 49 and the user-defined datums are numbered 50 and 51. The user instructs the GPS receiver which datum to use by sending the Datum Select command.
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VP ONCORE COMMAND REFERENCE DATUM SELECT (@@Ao) Motorola Binary Format Input Command • Query Current Datum ID Number: @@AoxC x - $ff (one byte, hex ff) C - checksum Message Length: 8 bytes • Change Datum ID Number: @@AodC d - Datum ID C – checksum Message Length: 8 bytes Response Message • 1 ..
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VP ONCORE COMMAND REFERENCE Back to Index SET USER DEFINED DATUM (@@Ap) The Motorola VP GPS receiver may have two user-defined datums stored in Datum ID numbers 50 and 51. The following commands allow the user to define the constants used for custom datums by supplying values for the semi-major axis; an inverse flattening constant; and deltaX, delta-Y, and delta-Z parameters. Default : 47 Datums 50 and 51are factory set to WGS-84 parameters.
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VP ONCORE COMMAND REFERENCE SET USER DEFINED DATUM (@@Ap) Motorola Binary Format Input Command • Request Current User Defined Datum Parameters: @@ApdxxxxxxxxxxxxxxxxxC d - Desired User Datum 50 or 51 xxxxxxxxxxxxxxxxx (17 bytes, all hex 00) C - checksum Message Length: 25 bytes • Define User Defined Datum Parameters: @@ApdsssffiiffffxxyyZzC d - Datum ID sssff - semi-major axis sss - integer part (meters) ff - fractional part (meters) iiffff - inverse flattening ii - integer part ffff -
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VP ONCORE COMMAND REFERENCE SET USER DEFINED DATUM (@@Ap) Motorola Binary Format Response Message • (to either command): @@ApdsssffliffffxxyyzzC d - Datum ID sssff - semi-major axis sss - integer part (meters) ff - fractional part (meters) iiffff - inverse flattening ii - integer part ffff - fractional part xx – delta-X (0.1 meter resolution) yy – delta-Y (0.1 meter resolution) zz –delta-Z (0.1 meter resolution) C - checksum Message Length: 25 bytes 49 Synergy Systems, LLC 05OCT01 50 ..
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VP ONCORE COMMAND REFERENCE Back to Index IONOSPHERIC CORRECTION MODE (@@Aq) The user has the flexibility of turning the GPS ionospheric correction models on or off. The models do a reasonable job of taking out the range error induced by the earth's ionosphere by using algorithms and parameters transmitted to the users by the satellites. For some applications, such as differential systems, the atmospheric models should be disabled since the differential corrections include the atmospheric errors.
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VP ONCORE COMMAND REFERENCE IONOSPHERIC CORRECTION MODE (@@Aq) Motorola Binary Format Input Command • Request current Ionospheric Correction Mode: @@AqxC x - 1 out of range hex byte C - checksum Message length: 8 bytes • $ff Change current Ionospheric Correction Mode: @@AqsC s - selection 0 = disabled 1 = enabled C - checksum Message length: 8 bytes Response Message • (to either command) @@AqsC s - selection 0 = disabled 1 = enabled C - checksum Message length: 8 bytes
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VP ONCORE COMMAND REFERENCE Back to Index POSITION FIX ALGORITHM TYPE (@@Ar) The VP receiver uses a least-squares position computation algorithm, and operates in one of two Position Fix modes as set by the user: Best-4 or N-in-View. Best-4: When enabled, the GPS receiver uses the best four satellites out of N satellites that the GPS receiver can track for the computation of position, where N is the number of satellites that the receiver is currently tracking.
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VP ONCORE COMMAND REFERENCE POSITION FIX ALGORITHM TYPE (@@Ar) Motorola Binary Format Input Command • Request Current Position Fix Algorithm Type: @@ArxC x - $ff (one byte, hex ff) C - checksum Message Length: 8 bytes • Change Position Fix Algorithm Type: @@ArsC s – selection 0 - Best-4 1 - N-in-View C - checksum Message Length: 8 bytes Response Message • (to either command): @@ArsC s - selection 0 - Best-4 1 - N-in-View C - checksum Message Length: 8 bytes 53 Synergy
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VP ONCORE COMMAND REFERENCE Back to Index POSITION-HOLD POSITION (@@As) Note: The input/output messages detailed here are available only if VP receiver Options ‘A’, ‘B’, or ‘I’ are installed. The user can specify receiver coordinates for Position-Hold applications such as timing to increase the timing accuracy, and real-time differential master station applications. This command is used to enter the position to be held.
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VP ONCORE COMMAND REFERENCE POSITION-HOLD POSITION (@@As) Motorola Binary Input Command • Request current Position-Hold Position @@AsxxxxxxxxxxxxxC xxxxxxxxxxxxx - 13 out of range bytes $7fffffff7fffffff7fffffffff C - checksum Message length: 20 bytes • Change current Position-Hold Position: @@AslllloooohhhhtC llll - latitude in mas oooo - longitude in mas hhhh - height in cm t - height type -324,000,000 .. 324,000,000 (-90º.. 90º) -648,000,000 .. 648,000,000 (-180º .. 180º) -100000 ..
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VP ONCORE COMMAND REFERENCE Back to Index POSITION-HOLD MODE SELECT (@@At) NOTE: The input/output messages described here available only if VP receiver options ‘A’, ‘B’, or ‘I’ are installed. The Position-Hold Mode Select command enables/disables the position-hold function for timing and real time differential applications.
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VP ONCORE COMMAND REFERENCE POSITION-HOLD MODE SELECT (@@At) Motorola Binary Format Input Command • Request current Position-Hold mode: @@AtxC x - 1 out of range byte C - checksum Message length: 8 bytes • $ff Change current Position-Hold Mode: @@AtmC m - mode 0 = disabled 1 = enabled C - checksum Message length: 8 bytes Response Message • (to either command) @@AtmC m - mode C - checksum Message length: 8 bytes 57 Synergy Systems, LLC 05OCT01 0 = disabled 1 = enabled
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VP ONCORE COMMAND REFERENCE Back to Index ALTITUDE-HOLD HEIGHT (@@Au) The user can specify the receiver height for manual altitude-hold applications. Use the Altitude-Hold Mode command to enable or disable the altitude-hold feature. The Altitude-Hold Height is specified in units of meters to a resolution of 0.01 meters. The user can reference the height parameter to the GPS reference ellipsoid or to Mean Sea Level.
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VP ONCORE COMMAND REFERENCE ALTITUDE-HOLD HEIGHT (@@Au) Motorola Binary Format Input Command • Request current Altitude-Hold Height: @@AuxxxxxC xxxxx - 5 out of range bytes $ffffffffff C - checksum Message length: 12 bytes • Change current Altitude-Hold Height: @@AuhhhhtC hhhh - height in cm t - height type -100,000 .. 1,800,800 (-1000.00 to +18,000.
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VP ONCORE COMMAND REFERENCE Back to Index ALTITUDE-HOLD SELECT (@@Av) The user can specify a height coordinate for altitude-hold applications. This command allows the user to manually enable or disable the altitude-hold feature. Remember, the GPS receiver automatically holds the altitude to the last known height when the xDOP is greater than the value entered with the 3D to 2D xDOP Threshold command (@@Al), or when the GPS receiver is tracking only three satellites.
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VP ONCORE COMMAND REFERENCE ALTITUDE-HOLD SELECT (@@Av) Motorola Binary Format Input Command • Request current Altitude-Hold Mode: @@AvxC x - 1 out of range byte C – checksum Message length: 8 bytes • $ff Change current Altitude-Hold Mode: @@AvmC m - mode 0 = disabled 1 = enabled C - checksum Message length: 8 bytes Response Message • (to either command) @@AvmC m - mode C - checksum Message length: 8 bytes 61 Synergy Systems, LLC 05OCT01 0 = disabled 1 = enabled
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VP ONCORE COMMAND REFERENCE Back to Index UTC/GPS TIME MODE SELECT (@@Aw) This command selects the type of time (either GPS or UTC) to be output in the Position/Status/Data Message and to be used as the synchronization point for the 1PPS timing pulse for timing receivers. See Time RAIM Setup and Status Messages (@@Bn or @@En.) Note that if the receiver does not have the UTC parameters portion of the almanac, then UTC will be output as being equal to GPS time.
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VP ONCORE COMMAND REFERENCE UTC/GPS TIME MODE SELECT (@@Aw) Motorola Binary Format Input Command • Request current Time Mode: @@AwxC x - 1 out of range hex byte ($ff) C - checksum Message length: 8 bytes • Change current Time Mode: @@AwmC m – mode 0 = GPS 1 = UTC C - checksum Message length: 8 bytes Response Message • (to either command) @@AwmC m – mode 0 = GPS 1 = UTC C - checksum Message length: 8 bytes 63 Synergy Systems, LLC 05OCT01
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VP ONCORE COMMAND REFERENCE Back to Index MEASUREMENT EPOCH OFFSET OPTION (@@Ax) NOTE: The input/output messages described here are available only if VP receiver Option ‘A’ or ‘I’ is installed. The VP receiver computes a position relative to a measurement epoch that occurs once per second. The receiver can place the measurement epoch on any of 1000 one-millisecond measurement sample points.
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VP ONCORE COMMAND REFERENCE MEASUREMENT EPOCH OFFSET OPTION (@@Ax) Motorola Binary Format Input Command • Send Current Measurement Epoch Offset: @@AxxxC xx - $ffff (two bytes, all hex ff) C - checksum Message Length: 9 bytes • Change Current Measurement Epoch Offset: @@AxttC tt - Time offset in milliseconds C - checksum Message Length: 9 bytes Response Message • 0.. 999 (0.000 to 0.
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VP ONCORE COMMAND REFERENCE Back to Index 1PPS TIME OFFSET COMMAND (@@Ay) NOTE: The input/output messages described here are available only if VP Options ‘A’ or ‘I’ are installed. The VP computes position relative to a measurement epoch that occurs once per second. In addition, the receiver outputs a one pulse-persecond (1PPS) signal, the rising edge of which is placed on top of the GPS/UTC one-second tic mark epoch.
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VP ONCORE COMMAND REFERENCE 1PPS TIME OFFSET COMMAND (@@Ay) Motorola Binary Format Input Command • Query Current 1PPS offset @@AyxxxxC xxxx - $ffffffff (four bytes, all hex ff) C - checksum Message Length: 11 bytes • Change Current 1PPS offset: @@AyttttC tttt -Time offset resolution = 1 nsec C - checksum Message Length: 11 bytes Response Message • 0 .. 999999999 (0.0 .. 0.
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VP ONCORE COMMAND REFERENCE Back to Index 1PPS CABLE DELAY OPTION (@@Az) NOTE: The input/output messages described here are available only if VP Options ‘A’ or ‘I’ are installed. The GPS receiver outputs a 1PPS signal, the rising edge of which is placed on top of the GPS/ UTC one-second tic mark epoch. The 1PPS Cable Delay offset allows the user to offset the one-pulse-per-second time mark in one nanosecond increments relative to the Measurement Epoch.
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VP ONCORE COMMAND REFERENCE 1PPS CABLE DELAY OPTION (@@Az) Motorola Binary Format Input Command • Query Current 1PPS offset @@AzxxxxC xxxx - $ffffffff (four bytes, all hex ff) C - checksum Message Length: 11 bytes • Change Current 1PPS offset: @@AzttttC tttt -Time offset resolution = 1 nsec C - checksum Message Length: 11 bytes Response Message • 0 .. 999999 (0.0 .. 0.
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VP ONCORE COMMAND REFERENCE Back to Index 6 CHANNEL POSITION/STATUS/DATA OUTPUT MESSAGE (@@Ba) The input command sets the rate at which the 6-Channel Position/Status/Data Message is output by the VP receiver. The mode parameter (m) in the input message instructs the GPS receiver to either output this message one time (polled), or to output this message at the indicated update rate (continuously).
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VP ONCORE COMMAND REFERENCE 6 CHANNEL POSITION/STATUS/DATA OUTPUT MESSAGE (@@Ba) Motorola Binary Format Input Command • Set response message rate: @@BamC m – mode 0 - output response message once 1..
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VP ONCORE COMMAND REFERENCE 6 CHANNEL POSITION/STATUS/DATA OUTPUT MESSAGE (@@Ba) continued Velocity vv - velocity in cm/s hh – heading (true north - res 0.1o) Geometry dd - current DOP (0.1 res) t - DOP type 0 .. 51400 (0 to 514.00 m/s) 0 .. 3599 (0.0 to 359.9o) 0 .. 999 (0.0 to 99.
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VP ONCORE COMMAND REFERENCE 6 CHANNEL POSITION/STATUS/DATA OUTPUT MESSAGE (@@Ba) continued d - Channel Status Flag Each bit represents one of the following: (msb) Bit 7: Using for Position Fix Bit 6: Satellite Momentum Alert Flag Set Bit 5: Satellite Anti-Spoof Flag Set Bit 4: Satellite Reported Unhealthy Bit 3: Satellite Reported Inaccurate (>16 m) Bit 2: Spare Bit 1: Spare (lsb) Bit 0: Parity Error (End of Channel Dependent Data) s - Receiver Status Message (msb) (lsb) C - checksum Message Length: 68 by
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VP ONCORE COMMAND REFERENCE Back to Index SATELLITE VISIBILITY STATUS MESSAGE (@@Bb) This command requests the results of the most current satellite alert computation. The response message gives a summary of the satellite visibility status showing the number of visible satellites, the Doppler frequency and the location (azimuth and elevation) of the currently visible satellites. The reference position for the most recent satellite alert is the current position coordinates.
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VP ONCORE COMMAND REFERENCE VISIBLE SATELLITE STATUS MESSAGE (@@Bb) Motorola Binary Format Input Command • Request current Satellite Visibility Status: @@BbmC m – mode 0 = output response message once (polled) 1 = output response message when visibility data changes C - checksum Length: 8 bytes Response Message • (to above command) @@Bbniddeaasiddeaasiddeaasiddeaas iddeaasiddeaasiddeaasiddeaasiddeaas iddeaasiddeaasiddeaasC n - number of visible sats 0 - 12 For each visible satellite,
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VP ONCORE COMMAND REFERENCE Back to Index 6 CHANNEL xDOP TABLE STATUS MESSAGE (@@Bc) This command requests the xDOP parameters corresponding to combinations of currently visible satellites based on the latest satellite visibility calculation. The VP receiver will send up to nine combinations of satellites with the corresponding xDOP parameter. The DOP type is selected by the user using the xDOP Type Parameter message (@@Aj.
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VP ONCORE COMMAND REFERENCE 6 CHANNEL xDOP TABLE STATUS MESSAGE (@@Bc) Motorola Binary Format Input Command • Request xDOP Table Status: @@BcmC m – mode 0 - output response message once (polled) 1 - output response message when data changes (continuous) C - checksum Message Length: 8 bytes Response Message • (to command) @@Bctnmddssssssddssssssddssssss ddssssssddssssssddssssssddssssss ddssssssddssssssC t - xDOP Type n - number of valid combinations m - Best-4 or N-in-View 0 - GDOP
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VP ONCORE COMMAND REFERENCE Back to Index ALMANAC STATUS MESSAGE (@@Bd) This command requests the almanac status information corresponding to the currently used satellite almanac data (in RAM), as well as the almanac data currently stored in receiver nonvolatile memory (EEPROM). The GPS receiver captures a new almanac to internal RAM first and uses this data immediately to compute satellite visibility information. The receiver also copies the RAM data to nonvolatile EEPROM using a slow background process.
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VP ONCORE COMMAND REFERENCE ALMANAC STATUS MESSAGE (@@Bd) Motorola Binary Format Input Command • Request Almanac Status: @@BdnC m - mode 0 - Output status once (polled) 1 - Output status when RAM almanac data changes (continuous) C - checksum Message Length: 8 bytes Response Message • (to command): @@BdvwtassssvwtassssC RAM Almanac Status – v - Almanac valid flag 0 - no almanac in receiver 1 - valid almanac in receiver w - almanac week 0 ..
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VP ONCORE COMMAND REFERENCE Back to Index ALMANAC DATA OUTPUT MESSAGE (@@Be) This parameter determines the rate the almanac data is output. The user has the option of requesting the almanac data output one time (polled), or each time the almanac data changes (continuously).
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VP ONCORE COMMAND REFERENCE ALMANAC DATA OUTPUT MESSAGE (@@Be) Motorola Binary Format Input Command • Set Almanac Data Output Rate: @@BemC m – mode 0 - output response message once (polled) 1 - output response message when almanac data changes (continuous) C - checksum Message Length: 8 bytes Response Message • (to command) @@Cbspxxxxx ... xxxxc sp – subframe/page Number xxx...
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VP ONCORE COMMAND REFERENCE Back to Index INPUT EPHEMERIS DATA (@@Bf) This command will cause the receiver to accept satellite ephemeris data input via the serial port. The receiver keeps the ephemerides decoded from all satellites in memory as long as backup voltage is applied to the receiver, and the ephemerides are still valid (t-toe < 4 hours).
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VP ONCORE COMMAND REFERENCE INPUT EPHEMERIS DATA (@@Bf) Motorola Binary Format Input Command • Input satellite ephemeris data: @@Bfixxx...xxxC i - sat ID xxx... xxx ephemeris 1 .. 37 sf 1 - 3/words 3 - 10 (72 bytes per sat; format per ICD-GPS-200) C - checksum Message Length: 80 bytes Response Message • (to command) @@Ccixxx...xxxC i - Sat ID xxx... xxx ephemeris 1 ..
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VP ONCORE COMMAND REFERENCE Back to Index 6 CHANNEL SATELLITE RANGE DATA OUTPUT MESSAGE (@@Bg) NOTE: The input/output messages described here are available only if GPS receiver Option C is installed. This parameter determines the rate that basic satellite range and rangerate information for each of the satellites that the VP receiver is tracking is output. The user has the option of requesting the satellite range data status one time, (polled) or continuously at a user specified update rate.
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VP ONCORE COMMAND REFERENCE 6 CHANNEL SATELLITE RANGE DATA OUTPUT MESSAGE (@@Bg) Motorola Binary Format Input Command • Set response message rate: @@BgmC m – mode 0 - output response message once (polled) 1..
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VP ONCORE COMMAND REFERENCE 6 CHANNEL SATELLITE RANGE DATA OUTPUT MESSAGE (@@Bg) continued For each of six channels: i - satellite ID 0..
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VP ONCORE COMMAND REFERENCE 6 CHANNEL SATELLITE RANGE DATA OUTPUT MESSAGE (@@Bg) continued In the discussions that follow, the subscript (k) refers to the current measurement data, and the subscript (k-1) refers to the previous (1 second old) data.
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VP ONCORE COMMAND REFERENCE 6 CHANNEL SATELLITE RANGE DATA OUTPUT MESSAGE (@@Bg) continued The user can accurately calibrate the code discriminator output by using the fact that the long term average difference between subsequent code discriminator measurements will be equal to 1 quantum. K5, the calibration constant, varies slowly over time as a function of received signal to noise ratio and multipath. Typical values of K5 are between 0.5 and 1.5.
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VP ONCORE COMMAND REFERENCE Back to Index PSEUDORANGE CORRECTION OUTPUT MESSAGE (@@Bh) This parameter sets the rate at which pseudorange corrections are output from the Motorola VP GPS receiver using the binary @@Ce message format. The pseudorange correction response message allows the VP to be used as a master site receiver in a real-time differential system.
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VP ONCORE COMMAND REFERENCE PSEUDORANGE CORRECTION OUTPUT MESSAGE (@@Bh) Motorola Binary Format Input Command • Set response rate: @@BhmC m – mode 0 - output response message once (polled) 1 .. 255 - response message output at indicated rate (continuous) 1 - once per second 2 - once every two seconds 255 - once every 255 seconds C - checksum Message Length: 8 bytes Response Message • (to command): @@Cetttippprrdippprrdippprrdippprrdippprrd ippprrdC ttt - GPS time ref 0 ..
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VP ONCORE COMMAND REFERENCE Back to Index EPHEMERIS DATA OUTPUT MESSAGE (@@Bi) This parameter determines the rate that satellite ephemeris data is output. The user has the option of requesting the ephemeris data output one time (polled), or each time the satellite ephemeris data changes (continuously). The commanded satellite ephemeris data output rate is stored in RAM and is retained between power cycles if backup battery power is applied.
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VP ONCORE COMMAND REFERENCE EPHEMERIS DATA OUTPUT MESSAGE (@@Bi) Motorola Binary Format Input Command • Set Response Message Rate: @@BimC m – mode 0 - output response message once (polled) 1 - output response message when ephemeris data changes (continuous) C - checksum Message Length: 8 bytes Response Message • (to command): @@Bfixxxxx ... xxxxC i - Sat ID xxx ... xxx - Ephemeris 1..
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VP ONCORE COMMAND REFERENCE Back to Index LEAP SECOND PENDING STATUS (@@Bj) This command causes the receiver to send a message to the user indicating the status of any pending leap second corrections to UTC. If a leap second is pending, its direction is also indicated. This is a polledonly output message. Leap seconds are occasionally inserted in UTC and generally occur on midnight UTC June 30 or midnight UTC December 3 1.
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VP ONCORE COMMAND REFERENCE LEAP SECOND PENDING STATUS (@@Bj) Motorola Binary Format Input Command • Request current Leap Second Status: @@BjmC m - mode 0 = output response message once (polled) C - checksum Message length: 8 bytes Response Message • To above command: @@BjmC m - status 0 = no leap second pending 1 = addition of one second pending 2 = subtraction of one second pending C - checksum Message length: 8 bytes 94 Synergy Systems, LLC 05OCT01
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VP ONCORE COMMAND REFERENCE Back to Index 6 CHANNEL POSITION/STATUS/DATA EXTENSION MESSAGE (@@Bk) This message contains information that can be considered an extension of the data output in the @@Ba 6 Channel Position/Status/Data message. Some users may have applications requiring use of this data at the same rate as the 6 Channel Position/Status/Data message while other users may only need portions of this data at a much slower rate (e.g., magnetic variation).
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VP ONCORE COMMAND REFERENCE 6 CHANNEL POSITION/STATUS/DATA EXTENSION MESSAGE (@@Bk) Motorola Binary Format Input Command • Request extension message: @@BkmC m - mode 0 - output response message once (polled) 1 ..
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VP ONCORE COMMAND REFERENCE 6 CHANNEL POSITION/STATUS/DATA EXTENSION MESSAGE (@@Bk) continued Magnetic Variation mm - -1800 to +1800 (-180.0o to +180.0o) resolution = 0.1 positive angles are east negative angles are west Velocity in north, east, up coordinate system nn north - 32767 to 32767 (m/s) resolution = 0.1 ee east - 32767 to 32767 (m/s) resolution = 0.1 uu up - 32767 to 32767 (m/s) resolution = 0.
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VP ONCORE COMMAND REFERENCE 6 CHANNEL POSITION/STATUS/DATA EXTENSION MESSAGE (@@Bk) Age of differential correction data (for slave receiver) aa 0 to 65535 (resolution 0.1s) Receiver position in ECEF coordinate system (X, Y, Z) xxxx resolution = 0.01 meters yyyy resolution = 0.01 meters zzzz resolution = 0.01 meters URA for each of six receiver channels (6 elements) ras decoded from the GPS satellite message (0-15 is valid URA, 63 if not decoded yet) see NAVSTAR GPSICD-200, Section 20.3.3.3.1.
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VP ONCORE COMMAND REFERENCE Back to Index SATELLITE BROADCAST DATA MESSAGE (@@Bl) The Global Positioning System satellites each broadcast a 50 bits per second (BPS) data message called the Navigation data. The structure of each satellite data message consists of 1500 bits (transmission time is 30 seconds) distributed across 5 sub-frames (6 seconds each). Each subframe is further subdivided into ten 30 bit words, where each word consists of 24 bits of data and 6 bits of parity.
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VP ONCORE COMMAND REFERENCE SATELLITE BROADCAST DATA MESSAGE (@@Bl) Motorola Binary Format Input Command • Request Broadcast message: @@BlmC (Note: The second character is a lower case "L" not the number "1") m – mode 0 - Output Next Subframe Data when collected (polled) 1 - Output Next and Subsequent data Messages (continuous) C - checksum Message Length: 8 bytes Response Message • (to command) @@Blcispxxxxx... xxxxxxC c - channel number i - Satellite ID 1 .. 8 0 ..
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VP ONCORE COMMAND REFERENCE SATELLITE BROADCAST DATA MESSAGE (@@Bl) Note: 101 If a particular channel of the receiver is not assigned to a satellite, then the satellite PRN ID field (i) will be set to zero. If the receiver cannot decode any single word of a particular subframe, then the subframe number, page number, and data word fields will all be set to zero for that particular subframe.
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VP ONCORE COMMAND REFERENCE Back to Index 6 CHANNEL TIME RAIM SETUP AND STATUS MESSAGE (@@Bn) NOTE: The input/output messages described here are available only if VP receiver option ‘I’ is installed. The Motorola VP receiver uses the Time RAIM algorithm to exploit redundancy in the GPS time solution in order to detect and isolate faulty satellites. The Time RAIM Setup and Status Message allows the user to change the update rate, the configuration for the 1PPS output, and the Time RAIM alarm limit.
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VP ONCORE COMMAND REFERENCE 6 CHANNEL TIME RAIM SETUP AND STATUS MESSAGE (@@Bn) continued than 99.99%, which corresponds to less than one missed detection per every 10,000 failures. Given the infrequency of GPS satellite failures, this makes a missed detection virtually impossible. The probability of a false alarm is less than 2.e-4%, which corresponds to less than one false alarm every 5.7 days.
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VP ONCORE COMMAND REFERENCE 6 CHANNEL TIME RAIM SETUP AND STATUS MESSAGE (@@Bn) continued Motorola Binary Format Input Command • Send current Time RAIM Setup and Status: @@BnxxxxxxxxxxxxxxxC x - 15 out of range bytes C - checksum Message length: 22 bytes • $ff ff ff ff ...
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VP ONCORE COMMAND REFERENCE 6 CHANNEL TIME RAIM SETUP AND STATUS MESSAGE (@@Bn) continued Response Message • (to either command): @@Bnotaapnnnmdyyhmspysreensffffsffff sffffsffffsffffsffffC o - output message rate t - Time RAIM algorithm on/off aa - Time RAIM alarm limit in 100s of nanoseconds p - 1PPS control mode nnn - 1PPS output rate mdyyhms - time to next fire m - months d - days yy - years h - hours m - minutes s - seconds p - pulse status 0.. 255 0 = off 1 = on 3 ..
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VP ONCORE COMMAND REFERENCE 6 CHANNEL TIME RAIM SETUP AND STATUS MESSAGE (@@Bn) continued r - Time RAIM status 0 = detection and isolation possible 1 = detection only possible 2 = neither possible 0 .. 65535 ee - time solution one sigma accuracy estimate in nanoseconds n - negative sawtooth -128 ..
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VP ONCORE COMMAND REFERENCE Back to Index 6 CHANNEL SELF-TEST (@@Ca) The VP GPS receiver user has the ability to perform an extensive self-test.
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VP ONCORE COMMAND REFERENCE 6 CHANNEL SELF-TEST (@@Ca) Motorola Binary Format Input Command • Initiate 6 Channel Self-Test: @@CaC C - checksum Message length: 7 bytes Response Message • (To command) @@CaxxC xx - self test result Two bytes as detailed below.
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VP ONCORE COMMAND REFERENCE Back to Index ALMANAC DATA INPUT MESSAGE (@@Cb) This input data command loads an almanac into the receiver's nonvolatile memory via the serial port. The entire almanac data message consists of 34 unique formatted messages that correspond to the subframe and page number of the almanac data (see GPS-ICD-200 for format description). The VP echoes the input almanac data subframe and page numbers of messages received so the user can validate that each almanac slice has been accepted.
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VP ONCORE COMMAND REFERENCE ALMANAC DATA INPUT MESSAGE (@@Cb) Motorola Binary Format Input Command • Input one Almanac Data page: @@Cbspxxx ... xxxC sp - subframe/page number xxx….
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VP ONCORE COMMAND REFERENCE Back to Index 6-CHANNEL ALERT PLANNING (@@Cd) This utility command allows the user to compute satellite visibility information for other locations than the GPS receiver's current location. This can be accomplished in either the Idle or the Position Fix modes.
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VP ONCORE COMMAND REFERENCE 6-CHANNEL ALERT-PLANNING (@@Cd) Motorola Binary Format Input Command • Initiate 6 Channel Alert Planning: @@CdmdyyhmsggaaaaoooohhinC Date m - month d - day yy - year Time h – hours m – minutes GMT Correction s - sign of GMT corr 1 .. 12 1 .. 31 1980 .. 2079 0 .. 23 0 .. 59 00 = positive FF = negative gg - GMT Correction (hrs, mm) hrs: 0 .. 12 min: 0 .. 59 Position aaaa - latitude (in mas) -324,000,000 ..
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VP ONCORE COMMAND REFERENCE 6-CHANNEL ALERT-PLANNING (@@Cd) continued Response Message • (to command): @@Cdmdyyhmniddeaasiddeaasiddeaas iddeaasiddeaasiddeaasiddeaasiddeaas iddeaasiddeasiddeaasiddeaastddssssss ddssssssddssssssddssssssddssssssddssssss ddssssssddssssssddssssssC Date m – month d – day yy - year Time h-hours m - minutes 1 .. 12 1 .. 31 1980 .. 2079 0..23 0.. 59 Satellite Visibility Information n - number of visible sats 0 ..
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VP ONCORE COMMAND REFERENCE Back to Index PSEUDORANGE CORRECTION INPUT (@@Ce) NOTE: The input/output messages described here are available only if VP Option ‘B’ is installed. Enabling this option allows the VP to accept pseudorange correction messages from a differential master site receiver. The input message is structured to accept pseudorange and pseudorange-rate corrections for up to six satellites.
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VP ONCORE COMMAND REFERENCE PSEUDORANGE CORRECTION INPUT (@@Ce) Motorola Binary Format Input Command • Input Pseudorange Corrections (for up to six satellites): @@Cetttippprrdippprrdippprrdippprrd ippprrdi ppprrdC ttt - GPS time ref i - sat ID 0 .. 6047999 (0.0 .. 604799.9) 0 .. 37 0 = not used 1-37 = sat ID ppp - pseudorange corr -1,048,576 .. +1,048,576 0.01 meter resolution (-10485.76 .. +10485.76 m) rr - pseudorange-rate corr -4096 .. 4096 0.001 m/s resolution (-4.096 .. 4.
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VP ONCORE COMMAND REFERENCE Back to Index SET-TO-DEFAULTS (@@Cf) This command sets all of the GPS receiver parameters to their default values. Performance of this utility results in all continuous messages being reset to polled only output, and clears the almanac and ephemeris data. The time and date stored in the internal real-time clock are not changed by the execution of this utility.
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VP ONCORE COMMAND REFERENCE SET-TO-DEFAULTS (@@Cf) Motorola Binary Format Input Command • Set receiver to Default values: @@CfC C - checksum Message length: 7 bytes Response Message • To above command: @@CfC C - checksum Message length: 7 bytes 117 Synergy Systems, LLC 05OCT01
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VP ONCORE COMMAND REFERENCE Back to Index POSITION FIX/IDLE MODE SELECT(@@Cg) This utility allows the user to place the VP receiver into one of two possible operating modes: Position Fix or Idle mode. The Position Fix mode is the normal operating mode of the VP receiver in which it acquires and tracks satellites and computes position from the satellite measurements. The Idle mode is a reduced power mode in which the VP does not track satellites.
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VP ONCORE COMMAND REFERENCE POSITION IDLE/FIX MODE SELECT (@@Cg) Motorola Binary Format Input Command • Select Operating Mode: @@CgmC m – mode 0 – Go to Idle mode 1 – Go to Position Fix mode 2 – Send current receiver mode C - checksum Message length: 7 bytes Response Message • To above command: @@CgmC m – mode 0 – Idle mode 1 – Position Fix mode C - checksum Message length: 7 bytes 119 Synergy Systems, LLC 05OCT01
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VP ONCORE COMMAND REFERENCE Back to Index SWITCH I/O FORMAT (@@Ci) This command switches the serial data format on the primary port from Motorola binary to one of the other embedded formats (either NMEA 0183 or Loran Emulation.
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VP ONCORE COMMAND REFERENCE SWITCH I/O FORMAT (@@Ci) Motorola Binary Format Input Command • Set Output Format to Desired Mode: @@CimC m - format 1 = NMEA 0183 (4800 baud) 2 = Loran Emulation (1200 baud) C - checksum Message length: 8 bytes Response Message 121 • There is no binary response to this command Synergy Systems, LLC 05OCT01
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VP ONCORE COMMAND REFERENCE Back to Index RECEIVER ID MESSAGE (@@Cj) The GPS receiver outputs an ID message upon request. The information contained in the ID string is self-explanatory.
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VP ONCORE COMMAND REFERENCE RECEIVER ID MESSAGE (@@Cj) Motorola Binary Format Input Command • Request Receiver ID String: @@CjC C - checksum Message length: 7 bytes Response Message • Response to command: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 @ @ C j (cr) (lf) C O P Y R I G H T M O T O R O L A # I N C .
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VP ONCORE COMMAND REFERENCE Back to Index 8 CHANNEL POSITION/STATUS/DATA MESSAGE (@@Ea) This input command sets the rate that the 8 Channel Position/Status/Data information in the response message is output. The mode parameter (m) in the input message instructs the GPS receiver to either output this message one time (polled), or to output this message at the indicated update rate (continuously).
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VP ONCORE COMMAND REFERENCE 8 CHANNEL POSITION/STATUS/DATA MESSAGE (@@Ea) Motorola Binary Format Input Command • Set Message Response Rate: @ @ Ea m C < C R > < L F > m - mode 0 = output response message once (polled) 1 ..
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VP ONCORE COMMAND REFERENCE 8 CHANNEL POSITION/STATUS/DATA MESSAGE (@@Ea) continued Velocity vv - velocity in cm/s hh - heading (true north res 0.1º) 0 .. 51,400 (0 .. 514.00 m/s) 0 .. 3,599 (0.0 .. 359.9º) Geometry dd - current DOP (0.1 res) 0 .. 999 (0.0 to 99.9 DOP) (0 = not computable, position-hold, or position propagate) t - DOP type 0 = PDOP (have 3D fix) 1 = HDOP (have 2D fix) Satellite visibility and tracking status n - num of visible sats 0 .. 12 t - num of satellites tracked 0 ..
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VP ONCORE COMMAND REFERENCE Back to Index 8 CHANNEL xDOP TABLE STATUS MESSAGE (@@Ec) This command requests the xDOP parameters corresponding to combinations of currently visible satellites based on the latest satellite visibility calculation. The VP receiver will send up to nine combinations of satellites with the corresponding xDOP parameter. The DOP type is selected by the user using the xDOP Type Parameter message (@@Aj.
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VP ONCORE COMMAND REFERENCE 8 CHANNEL xDOP TABLE STATUS MESSAGE (@@Ec) Motorola Binary Format Input Command • Request xDOP Table Status: @@EcmC m – mode 0 - output response message once (polled) 1 - output response message when data changes (continuous) C - checksum Message Length: 8 bytes Response Message • (to command) @ @ Ec t n m d d s s s s s s d d s s s s s s d d s s s s s s ddssssssddssssssddssssssddssssss ddssssssddssssssC t - xDOP Type n - number of valid combinations m - B
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VP ONCORE COMMAND REFERENCE Back to Index 8 CHANNEL SATELLITE RANGE DATA OUTPUT MESSAGE (@@Eg) NOTE: The input/output messages described here are available only if GPS receiver Option C is installed. This parameter determines the rate that basic satellite range and rangerate information for each of the satellites that the VP receiver is tracking is output. The user has the option of requesting the satellite range data status one time, (polled) or continuously at a user specified update rate.
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VP ONCORE COMMAND REFERENCE 8 CHANNEL SATELLITE RANGE DATA OUTPUT MESSAGE (@@Eg) Motorola Binary Format Input Command • Set response message rate: @@EgmC m – mode 0 - output response message once (polled) 1..
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VP ONCORE COMMAND REFERENCE 8 CHANNEL SATELLITE RANGE DATA OUTPUT MESSAGE (@@Eg) continued For each of eight channels: i - satellite ID 0..
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VP ONCORE COMMAND REFERENCE 8 CHANNEL SATELLITE RANGE DATA OUTPUT MESSAGE (@@Eg) continued In the discussions that follow, the subscript (k) refers to the current measurement data, and the subscript (k-1) refers to the previous (1 second old) data.
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VP ONCORE COMMAND REFERENCE 8 CHANNEL SATELLITE RANGE DATA OUTPUT MESSAGE (@@Eg) continued Typical values of K5 are between 0.5 and 1.5. A simple low-pass filter can be used to generate K5 as follows: diff = K3 * abs (CDk – CDk-1) CDk-1 = CDk LPF = LPF + beta * (diff - LPF) K5 = 10.4662 / LPF (initialize LPF = 10.4662 meters) The constant "beta" establishes the filter time constant. Typical values of beta are 0.001 (maximum filtering) to 0.5 (minimum filtering). The Oncore uses a constant of 0.
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VP ONCORE COMMAND REFERENCE Back to Index 8 CHANNEL POSITION/STATUS/DATA EXTENSION MESSAGE (@@Ek) This message contains information that can be considered an extension of the data output in the @@Ea 8 Channel Position/Status/Data message. Some users may have applications requiring use of this data at the same rate as the @@Ea message while other users may only need portions of this data at a much slower rate (e.g., magnetic variation).
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VP ONCORE COMMAND REFERENCE 8 CHANNEL POSITION/STATUS/DATA EXTENSION MESSAGE (@@Ek) Motorola Binary Format Input Command • Request extension message: @ @ Ek m C < C R > < L F > m - mode 0 - output response message once (polled) 1 ..
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VP ONCORE COMMAND REFERENCE 8 CHANNEL POSITION/STATUS/DATA EXTENSION MESSAGE (@@Ek) continued Magnetic Variation mm - -1800 to +1800 (-180.0o to +180.0o) resolution = 0.1 positive angles are east negative angles are west Velocity in north, east, up coordinate system nn north - 32767 to 32767 (m/s) resolution = 0.1 ee east - 32767 to 32767 (m/s) resolution = 0.1 uu up - 32767 to 32767 (m/s) resolution = 0.
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VP ONCORE COMMAND REFERENCE 8 CHANNEL POSITION/STATUS/DATA EXTENSION MESSAGE (@@Ek) Age of differential correction data (for slave receiver) aa 0 to 65535 (resolution 0.1s) Receiver position in ECEF coordinate system (X, Y, Z) xxxx resolution = 0.01 meters yyyy resolution = 0.01 meters zzzz resolution = 0.01 meters URA for each of eight receiver channels (8 elements) ras decoded from the GPS satellite message (0-15 is valid URA, 63 if not decoded yet) see NAVSTAR GPSICD-200, Section 20.3.3.3.1.
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VP ONCORE COMMAND REFERENCE Back to Index 8 CHANNEL TIME RAIM SETUP AND STATUS MESSAGE (@@En) NOTE: The input/output messages described here are available only if GPS receiver option ‘I’ is installed. The Motorola VP receiver uses the Time RAIM algorithm to exploit redundancy in the GPS time solution in order to detect and isolate faulty satellites. The Time RAIM Setup and Status Message allows the user to change the update rate, the configuration for the 1PPS output, and the Time RAIM alarm limit.
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VP ONCORE COMMAND REFERENCE 8 CHANNEL TIME RAIM SETUP AND STATUS MESSAGE (@@En) continued than 99.99%, which corresponds to less than one missed detection per every 10,000 failures. Given the infrequency of GPS satellite failures, this makes a missed detection virtually impossible. The probability of a false alarm is less than 2.e-4%, which corresponds to less than one false alarm every 5.7 days.
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VP ONCORE COMMAND REFERENCE 8 CHANNEL TIME RAIM SETUP AND STATUS MESSAGE (@@En) Motorola Binary Format Input Command • Send current Time RAIM Setup and Status: @@EnxxxxxxxxxxxxxxxC x - 15 out of range bytes C - checksum Message length: 22 bytes • $ff ff ff ff...
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VP ONCORE COMMAND REFERENCE 8 CHANNEL TIME RAIM SETUP AND STATUS MESSAGE (@@En) continued Response Message • (to either command): @@Enotaapnnnmdyyhmspysreensffffsffff sffffsffffsffffsffffsffffsffffC o - output message rate t - Time RAIM algorithm on/off aa - Time RAIM alarm limit in 100s of nanoseconds p - 1PPS control mode nnn - 1PPS output rate mdyyhms - time to next fire m - months d - days yy - years h - hours m - minutes s - seconds p - pulse status y - 1PPS pulse sync s - Time RAIM solutio
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VP ONCORE COMMAND REFERENCE 8 CHANNEL TIME RAIM SETUP AND STATUS MESSAGE (@@En) continued r - Time RAIM status 0 = detection and isolation possible 1 = detection only possible 2 = neither possible 0 .. 65535 ee - time solution one sigma accuracy estimate in nanoseconds n - negative sawtooth -128 .. 127 time error of next 1PPS pulse in nanoseconds For each of eight receiver channels s - satellite ID 0 .. 37 ffff - fractional GPS local 0 ..
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VP ONCORE COMMAND REFERENCE Back to Index 8 CHANNEL SELF-TEST (@@Fa) The VP GPS receiver user has the ability to perform an extensive self-test.
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VP ONCORE COMMAND REFERENCE 8 CHANNEL SELF-TEST (@@Fa) Motorola Binary Format Input Command • Initiate 8 Channel Self-Test: @@FaC C - checksum Message length: 7 bytes Response Message • (To command) @@FaxxC xx - self test result Two bytes as detailed below.
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VP ONCORE COMMAND REFERENCE Back to Index 8-CHANNEL ALERT-PLANNING (@@Fd) This utility command allows the user to compute satellite visibility information for other locations than the GPS receiver's current location. This can be accomplished in either the Idle or the Position Fix modes.
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VP ONCORE COMMAND REFERENCE 8-CHANNEL ALERT-PLANNING (@@Fd) Motorola Binary Format Input Command • Initiate 8 Channel Alert Planning: @@FdmdyyhmsggaaaaoooohhinC Date m - month d - day yy - year Time h – hours m – minutes GMT Correction s - sign of GMT corr 1 .. 12 1 .. 31 1980 .. 2079 0 .. 23 0 .. 59 00 = positive FF = negative gg - GMT Correction (hrs, mm) hrs: 0 .. 12 min: 0 .. 59 Position aaaa - latitude (in mas) -324,000,000 ..
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VP ONCORE COMMAND REFERENCE 8-CHANNEL ALERT-PLANNING (@@Fd) continued Response Message • (to command): @@Fdmdyyhmniddeaasiddeaasiddeaasiddeaas iddeaasiddeaasiddeaasiddeaasiddeaasiddeas iddeaasiddeaastddssssssssddssssssssddssss ssssddssssssssddssssssssddssssssssddsssss sssddssssssssddssssssssC Date m – month d – day yy - year Time h-hours m - minutes 1 .. 12 1 .. 31 1980 .. 2079 0..23 0.. 59 Satellite Visibility Information n - number of visible sats 0 ..