Garmin TracPak GPS 30/30 SL User manual

GPS 30/30 SL TracPakTM
GPS SMART ANTENNA
TECHNICAL SPECIFICATION
GARMIN · 1200 E. 151st Street · Olathe, Kansas 66062
[phone] · [phone] FAX

© 1995/1996 GARMIN Corporation, 1200 E. 151st Street,
Olathe, KS 66062
Allrightsreserved. Nopartofthismanualmaybereproduced
or transmitted in any form or by any means, electronic or
mechanical,includingphotocopyingandrecording,forany
purposewithouttheexpresswrittenpermissionofGARMIN.
Information in this document is subject to change without
notice. GARMIN reserves the right to change or improve
their products and to make changes in the content without
obligation to notify any person or organization of such
changes or improvements.
November, 1996 190-00088-00 Rev. E

CAUTION
The GPS system is operated by the government of the
United States which is solely responsible for its accuracy
and maintenance. Although the GPS 30/30 SL is a
precisionelectronicNAVigationAID(NAVAID),anyNAVAID
can be misused or misinterpreted, and therefore become
unsafe. UsetheGPS30/30SLatyourownrisk. Toreduce
therisk, carefullyreview andunderstand allaspects ofthis
Technical Manual before using the GPS 30/30 SL. When
in actual use, carefully compare indications from the GPS
30/30 SL to all available navigation sources including the
information from other NAVAIDs, visual sightings, charts,
etc. For safety, always resolve any discrepancies before
continuing navigation.
NOTE
This device has been tested and found to comply with the
limitsforaClass Bdigitaldevice, pursuanttoPart15 ofthe
FCC Rules. Operation is subject to the following two
conditions: (1) This device may not cause harmful
interference,and(2)thisdevicemustacceptanyinterference
received, including interference that may cause undesired
operation.
Thisdevicegenerates,usesandcanradiateradiofrequency
energyand,ifnotinstalledandusedinaccordancewiththe
instructions, may cause harmful interference to radio
communications. However, there is no guarantee that
interference will not occur in a particular installation. If this
devicedoescauseharmfulinterferencetoradioortelevision
reception, which can be determined by turning the device
off and on, you are encouraged to try to correct the
interference by one or more of the following measures:
· Reorient or relocate the receiving antenna.
· Increase the separation between this device and the
receiver.

· Connect this device to an outlet on a different circuit
than that to which the receiver is connected.
· Consultthedealeroranexperienceradio/TVtechnician
for help.
This device contains no user-serviceable parts. Repairs
should only be performed by an authorized GARMIN
service center. Unauthorized repairs or modifications to
this device could void your warranty and your authority to
operate this device under Part 15 regulations.

TABLE OF CONTENTS
1. Introduction 1
1.1 Overview 1
1.2 Features 2
1.3 Technical Specifications 2
1.4 Application 4
2. Operational Characteristics 6
2.1 Self Test 6
2.2 Initialization 6
2.3 Navigation 7
2.4 Satellite Data Collection 8
3. Hardware Interface 10
3.1 Mechanical Dimensions 10
3.2 Mounting Configurations and Options 11
3.3 Connection Wiring Description 15
4. Software Interface 17
4.1 NMEA Received Sentences 17
4.2 NMEA Transmitted Sentences 21
4.3 Baud Rate Selection 29
4.4 RTCM Received Data 30
A. Earth Datums A-1

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SECTION 1
INTRODUCTION
1.1 OVERVIEW
The GARMIN GPS 30/30 SL is a complete GPS receiver,
including an embedded antenna, designed for a broad
spectrum of OEM (Original Equipment Manufacturer)
system applications. Based on the proven technology
foundinallGARMINGPSreceivers,theGPS30/30SLwill
trackuptoeightsatellitesatatimewhileprovidingfasttime-
to-first-fix, one second navigation updates and low power
consumption. Itsfarreachingcapabilitymeetsthesensitivity
requirements of land navigation as well as the dynamics
requirements of high performance aircraft.
The GPS30/30SLdesignutilizesthelatesttechnologyand
highlevelcircuitintegrationtoachievesuperiorperformance
whileminimizingspaceandpowerrequirements. Allcritical
components of the system including the RF/IF receiver
hardware and the digital baseband are designed and
manufactured by GARMIN to ensure the quality and
capability of the GPS 30/30 SL. This hardware capability
combinedwithsoftwareintelligence makestheGPS30/30
SL easy to integrate and use.
TheGPS30/30SLisdesignedtowithstandruggedoperating
conditionsand iscompletelywater resistant. TheGPS 30/
30 SL is a complete GPS receiver that requires minimal
additional components be supplied by an OEM or system
integrator. A minimum system must provide the GPS 30/
30 SL with a source of power and a clear view of the GPS
satellites. ThesystemmaycommunicatewiththeGPS30/
30 SL via a choice of two RS-232 compatible full duplex
communicationchannels. Internalmemory backupallows
the GPS 30/30 SL to retain critical data such as satellite
orbital parameters, last position, date and time. End user
interfaces such as keyboards and displays are added by
the application designer.

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1.2 FEATURES
The GPS 30/30 SL provides a host of features that make
it easy to integrate and use.
1) Full navigation accuracy provided by Standard
Positioning Service (SPS).
2) Compact design ideal for applications with minimal
space.
3) High performance receiver tracks up to 8 satellites
while providing fast first fix and low power
consumption.
4) Differential capability utilizes real-time RTCM
correctionsproducing3-10meterpositionaccuracy.
5) Internalclockandmemoryaresustainedbyamemory
backup battery or optional external standby power.
6) User initialization is not required.
7) Navigation mode (2D or 3D) may be configured by
the user.
8) Two communication channels and user selectable
baud rates allow maximum interface capability and
flexibility.
9) The GPS 30 SL can be permanently configured by
the user. Configuration parameters include baud
rate, NMEA sentence output, velocity filter setting,
and datum selection.
1.3 TECHNICAL SPECIFICATIONS
Specifications are subject to change without notice.
1.3.1 Physical Characteristics
1) Single construction integrated antenna/receiver.
2) Weight: 4.4 oz, (124.5 g), not including cable

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3) Size: 2.230"(w) x3.796"(l)x1.047" (h), (56.64mm
x 96.42 mm x 26.60 mm)
1.3.2 Environmental Characteristics
1) Operating temperature: -30°C to +85°C (internal
temperature)
2) Storage temperature: -40°C to +90°C
1.3.3 Electrical Characteristics
1) Input voltage: 10 to 30 VDC, unregulated.
2) Typically draws 110 mA @ 12 VDC
3) Backup power: Internal 3V Lithium coin cell battery,
up to 10 year life
4) Receiver sensitivity: -160dBW minimum
1.3.4 Performance
1) MultiTracTM technology, tracks up to 8 satellites
2) Update rate: 1 second
3) Acquisition time
- 15 seconds warm (all data known)
- 2 minutes cold (initial position, time and almanac
known, ephemeris unknown)
- 7-10 minutes AutoLocateTM (almanac known,
initial position and time unknown)
- 15 minutes search the sky (no data known)
4) Position accuracy:
Differential GPS (DGPS): 3-10 meters RMS
Non-differentialGPS: 15metersRMS(100meters
with Selective Availability on)
5) Velocityaccuracy: 0.2m/sRMSsteadystate(subject
to Selective Availability)
6) Dynamics: 999 knots velocity, 3g dynamics

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1.3.5 Interfaces
1) DualchannelRS-232compatiblewithuserselectable
baud rate (1200, 2400, 4800, 9600)
2) NMEA 0183 Version 2.0 ASCII output: GPGGA,
GPGSA, GPGSV, GPRMC, GPVTG, PGRME,
PGRMT (GPS 30 SL - PGRMF, PGRMV, LCGLL,
LCVTG)
Inputs
- Initial position, date and time (not required)
- 2D/3D, earth datum and differential mode
configuration command
Outputs
- Position, velocity and time
- Receiver and satellite status
- Differential Reference Station ID and RTCM Data
age
- Geometry and error estimates
3) Real-timeDifferentialCorrectioninput(RTCMformat)
1.4 APPLICATION
TYPICAL APPLICATION ARCHITECTURE

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1.4.1 Application Considerations
1) Interruptions in GPS RF signals can increase the
Time To First Fix (TTFF). Antenna location with
continuousclearline-of-sightvisibilitytoalldirections
in the sky yields the best TTFF.
2) GPS signal reception quality can be determined by
monitoring the signal to noise ratio fields in the
$GPGSV sentence. Typical values will be between
33to51dbHz. Valuesbelow43dbHzforthehighest
elevation satellites may indicate a need to re-locate
the antenna if marginal performance is noted (long
TTFF).

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SECTION 2
OPERATIONAL CHARACTERISTICS
Thissectiondescribesthebasicoperationalcharacteristics
of the GPS 30/30 SL. Additional information regarding
input and output specifications are contained in Section 4.
2.1 SELF TEST
After input power has been applied to the GPS 30/30 SL
and periodically thereafter, the unit will perform critical self
test functions and report the results over the output
channel(s). The following tests will be performed:
1) RAM check
2) ROM test
3) Receiver test
4) Real-time clock test
5) Oscillator check
In addition to the results of the above tests, the GPS 30/30
SL will report software version information.
2.2 INITIALIZATION
After the initial self test is complete, the GPS 30/30 SL will
begintheprocessof satelliteacquisitionandtracking. The
acquisition process is fully automatic and, under normal
circumstances,willtakeapproximately2minutestoachieve
a 2D position fix and 2.5 minutes for 3D fixes (15 seconds
if ephemeris data is known). After a position fix has been
calculated,valid position,velocity andtime informationwill
be transmitted over the output channel(s).
LikeallGPSreceivers,theGPS30/30SLutilizesinitialdata
such as last stored position, date and time as well as

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satellite orbital data to achieve maximum acquisition
performance. If significant inaccuracy exists in the initial
data, or if the orbital data is obsolete, it may take from 5 to
15 minutes to achieve a navigation solution. The GPS 30/
30 SL AutoLocateTM feature is capable of automatically
determininganavigationsolutionwithoutinterventionfrom
thehostsystem. However,acquisitionperformancecanbe
improved if the host system initializes the GPS 30/30 SL
following the occurrence of one or more of the following
events:
1) Transportation over distances further than 1500
kilometers
2) Failureoftheinternalmemorybatterywithoutsystem
standby power
3) Stored date/time off by more than 30 minutes
See Section 4 for more information on initializing the GPS
30/30 SL.
2.3 NAVIGATION
After the acquisition process is complete, the GPS 30/30
SL will begin sending valid navigation information over its
output channels. These data include:
1) Latitude/longitude/altitude
2) Velocity
3) Date/time
4) Error estimates
5) Satellite and receiver status
NormallytheGPS30/30SLwillselecttheoptimalnavigation
mode(2Dor3D)basedonavailablesatellitesandgeometry
considerations. The host system, at its option, may
command the GPS 30/30 SL to choose a specific mode of
navigation,suchas2D. Thefollowingmodesareavailable:

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1) 2D exclusively with altitude supplied by the host
system (altitude hold mode)
2) 3D exclusively with altitude computed by the GPS
30/30 SL
3) Automatic mode in which the board set determines
the desired mode based on satellite availability and
geometry considerations
When navigating in the 2D mode (either exclusive or
automatic), the GPS 30/30 SL utilizes the last computed
altitude or the last altitude supplied by the host system,
whicheverisnewer. Thehost systemmustensurethatthe
altitude used for 2D navigation is accurate since the
resultingpositionerrormaybeaslargeasthealtitudeerror.
See Section 4 for more information on altitude control.
Operationintheexclusive3Dmodemaycauseundesirable
navigation outages due to satellite shading or limited
satellite availability. However, because the GPS 30/30 SL
tracksup toeight(8) satellitesin view,thiscondition willbe
minimal, as the GPS satellite constellation status has
reached initial operational capability.
The GPS 30/30 SL will default to automatic differential
corrections, attempting to apply them to the satellite data,
inordertoproduceadifferential(DGPS)solution. Thehost
system,atitsoption,mayalsocommandtheGPS30/30SL
to choose differential only mode. When navigating in the
differential only mode, the GPS 30/30 SL will output a
position only when a differential solution is available.
2.4 SATELLITE DATA COLLECTION
TheGPS30/30SLwillautomaticallyupdatesatelliteorbital
data as it operates. The intelligence of the GPS 30/30 SL
combined with its hardware capability allows these data to
be collected and stored without intervention from the host
system. A few key points should be considered regarding
this process:

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1) IftheGPS30/30SLisnotoperatedforaperiodofsix
(6) months or more, the unit will “search the sky” in
order to collect satellite orbital information. This
processisfullyautomaticbut thehostsystemshould
allowtheGPS30/30SLtoremainonforatleast12.5
minutesafterthefirstsatelliteisacquiredtocomplete
collecting almanac data (see Section 4 for more
information on status indications).
2) If the internal memory backup battery fails while the
host system power is off and not connected to
standbypower,theGPS30/30SLwillsearchthesky
asdescribedabove. Thesystemdesignershouldbe
awareoftheavailabilityofstandbypowerinputtothe
GPS 30/30 SL to prevent this situation.
3) If the initial data is significantly inaccurate, the GPS
30/30 SL will perform an operation known as
AutoLocateTM. Thisprocedureisfullyautomaticand,
undernormalcircumstances,willrequire4-10minutes
to calculate a navigation solution. AutoLocateTM,
unlikesearchthe sky,does notrequire thatthe GPS
30/30 SL continue to operate after a fix has been
obtained.

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SECTION 3
HARDWARE INTERFACE
3.1 MECHANICAL DIMENSIONS
The GPS 30/30 SL is a complete GPS receiver including
antenna in an uniquely styled waterproof package.

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3.2 MOUNTING CONFIGURATIONS AND OPTIONS
The following mounting options are available for the GPS
30/30 SL. Mounting is user configurable.
3.2.1. Magnetic Mount
The magnetic mount provides a firm, removable mounting
attachment to any ferrous metal surface.

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3.2.2 Trunk Lip Mount
Thetrunklipmountprovidesasemi-permanentattachment
to the trunk lip of most automobiles.

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3.2.3 Suction Cup Mount
The suction cup bracket provides a removable mounting
surface attached to the inside of a vehicle's windshield.

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3.2.4 Flange Mount
The flange mount allows for a permanent installation on a
flat surface. This mounting configuration is ideal in
applicationsinwhichthefarsideofthemountingsurfaceis
inaccessible.

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3.3 CONNECTION WIRING DESCRIPTION
TheGPS30/30SLfeaturesastrippedandpre-tinnedcable
assemblyforthegreatestconnectionflexibility. Thefollowing
isafunctionaldescriptionofeachwireinthecableassembly.
Red: VIN - Unregulated 10 - 30VDC 200mA
(maximum). Typical operating
current is 110 mA.
Black: GND - Power and Signal Ground
White: TXD1- FirstSerialAsynchronous Output.
RS-232compatibleelectricalspecification.
This output normally provides serial data
which is formatted per “NMEA 0183,
Version 2.0” . Switchable to 1200, 2400,
4800 and 9600 BAUD. This output
functionsinparallelwiththeNMEAoutput.
Blue: RXD1 - First Serial Asynchronous Input.
RS-232 compatible with maximum input
voltagerange-25<V<25. Thisinputmay
be used to receive serial initialization/
configurationdata,asspecifiedinSection
4.1.
Purple: TXD2 - Second Serial Asynchronous
Output. Electrically identical to TXD1.
Green: RXD2-SecondSerialAsynchronousInput.
Electrically identical to RXD1. This input
may be used to receive serial differential
GPS data formatted per “RTCM
RecommendedStandardsForDifferential
Navstar GPS Service, Version 2.0” (see
Section 4 for more details).
optional connection. Internal battery
capacity is 180 mA hour.