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SiRFDemo User Guide

1. See Navigation Library SV State Data Message ID 30 in the SiRF Binary Reference Manual for information about SiRF extended ephemeris tracking status messages The information displayed in the Signal Level view is also assisted by color coding As the tracking status of each satellite changes the associated text and signal levels are colored to represent the current status see Table 3 3 Table 3 3 12 Channel Signal Level View Color Coding Color Description Red The satellite location is known from almanac information however the satellite is not currently being tracked Blue The satellite is being tracked however it is not being used in the current position solution Green The satellite is being tracked and is being used in the current position solution Aqua For SBAS satellites only The satellite is being tracked and corrections are being used in the current position Magenta The satellite is being tracked however a SiRFInstantFix extended ephemeris is being used for the position solution SiRF Demo User Guide June 2007 Oo IH The Radar View Screen The Radar View screen graphically displays the location of each of the tracked used and available satellites in the form of a polar plot To display the Radar View screen 1 click the Radar View button or select Radar from the View menu Fa Radar Yiew In addition to the satellite locations the current tracking status is
2. Description Default Disable Displays true user movement due to SA and other environmental issues Yes such as multipath Enable Holds the current position as fixed when the user is in a stationary No mode Updates to the fixed position due to SA are made based on internal navigation data 3 Click Send to accept or Cancel to exit Note The Static Navigation filter is Disabled when DGPS corrections are used in the navigation solution Setting the DGPS Mode The DGPS mode is used to control the position output of a GPS receiver based on whether positions are differentially corrected To set the DGPS mode 1 Select DGPS Mode from the Navigation menu The DGPS Mode screen is displayed DGPS Mode Default X Mode Automatic Cancel O Exclusive C Never use Timeout sec 20 Using the SiRFDemo Software 3 61 3 62 2 Select the Mode that you want to use Description Default Automatic Use differential corrections when they are available otherwise compute On a non differential solution See the Note that follows Exclusive Only compute a differential solution When no corrections are available Off no solution is output Never use Only compute a non differential solution even when corrections are Off valid 3 Enter the timeout value in seconds you want to use in the Timeout field A received differential correction is applied to the solution until either the timeou
3. Cancel Ki 2 Specify the file name that you want to save the ephemeris information to 3 Click Save to save the data to file A message box 1s displayed to confirm completion To load an ephemeris file see Uploading an Ephemeris to a GPS Receiver on page 3 47 Polling the Ephemeris State Polling the ephemeris state sends msg 56 subID 3 and the response can be viewed by selecting Messages Response in the View menu The ephemeris state can also be polled by selecting Messages Ephemeris Info from the View menu which is graphically displays the message response See Ephemeris Information on page 3 29 SiRFDemo User Guide June 2007 Oo IH Polling the Extended Ephemeris The SiRFDRive Menu Using the SiRFDemo Software The Ext Eph Info menu item polls the currently loaded SiRF extended ephemeris for information about its download date age and valid time remaining To poll the currently loaded ephemeris file 1 Select Extended Ephemeris from the Poll menu The Extended Ephemeris Information screen is displayed Extended Eph Info x valid from 2006 02 28 Age 2d 20h 48 m Prediction interval 7d This section describes the SiRFDemo software functions under the SiRFDRive menu Navigation Mode Control Gyro Factory Calibration r DR Sensor s Paramters Poll Gyro Factory Calibration Poll Sensor s Parameters e Setting Navigation Mode Control on page 3 70 e
4. Operating M x Mormal C Testi D Test Cancel l Test 3 Test 4 7 2 Select Test 1 Test 2 Test 3 or Test 4 when you want to track a specific satellite on all channels and output test results Test 2 outputs additional data to that of Test 1 Note Test 1 Test 2 Test 3 and Test 4 enables Testmode 1 Testmode 2 and Testmode 3 data respectively For a full description of each testmode refer to the SiRF Binary Reference Manual 3 In the Period field enter the output rate of the test reports in seconds 4 Enter the SV number that you want to be tracked by all 12 channels of the GPS receiver 5 Select Normal default to track all available satellites 6 Click Send to send the command to the GPS receiver When the GPS receiver is changed to a test mode every channel on the receiver tracks only the satellite specified 3 49 3 50 This can be confirmed by viewing the 12 Channel Signal Level view Ey 12 Channel Signal Level Yiew 0 Disabling a Broadcast Ephemeris The Disable Broadcast Ephemeris is only available when GSWLT3 GSW3 2 or newer is selected as the target software in the Setup menu To disable a broadcast ephemeris Select Disable Broadcast Ephemeris from the Action menu 115iRFDemo 3 82 009ENG Target SW GSW3 1_3 1 00 03 C33E Setup View Gction Navigation Poll Window Ed img w Open Data Source Open Log File MET Put Text in Log File oy ot
5. SiRF SiRF Demo User Guide SiRF Technology Inc 217 Devcon Drive San Jose CA 95112 U S A Phone 1 408 467 0410 Fax 1 408 467 0420 www SiRF com Part Number 1050 0059 Revision 1 5 June 2007 SiRF SiRFStar SiRF plus orbit design are registered in the U S Patent and Trademark Office This document contains information on a product under development at SiRF The information is intended to help you evaluate this product SiRF reserves the right to change or discontinue work on this product without notice SiRF Demo User Guide Copyright 1996 2007 SiRF Technology Inc All rights reserved No part of this work may be reproduced or transmitted in any form or by any means electronic or mechanical including photocopying and recording or by any information storage or retrieval system without the prior written permission of SiRF Technology Inc unless such copying is expressly permitted by United States copyright law Address inquiries to Legal Department SiRF Technology Inc 217 Devcon Drive San Jose California 95112 United States of America About This Document This document contains information about SiRF products SiRF Technology Inc reserves the right to make changes in its products specifications and other information at any time without notice SiRF assumes no liability or responsibility for any claims or damages arising out of the use of this document or from the use of integrated circuits based on this do
6. The screen is divided into the following fields SiRFDRive 1 x SiRFDRive 2 x amp SiRFDiRect To view the SiRFDRive Sensor View screen 1 Select Messages SiRFDRive Sensor from the View menu The SiRFDRive Sensor View screen is displayed YSIRFDRive Sensor View SiRFDRive 2 x amp SiIRFDiRect Sensor Pkg Gyroscopes amp Accelerometers Sensor Data Type Yaw Rate Gyro Pitch Rate Gyro Down Accell Lon Accel x Lat Accelfy of Valid 10 Reverse Time 796090 Time 796190 Time 796290 Time 796390 Time 796490 Time 796590 Time 796690 Time 796790 Time 796390 Time 796990 Time 0 Validity 01111101 Gyro2 0 630 deg s Validity 01111101 Gyro2 0 630 deg s Validity 01111101 Gyro2 0 630 deg s Validity 01111101 Gyro2 0 630 deg s Validity 01111101 Gyro2 0 630 deg s Validity 01111101 Gyro2 0 630 deg s Validity 01111101 Gyro2 0 630 deg s Validity 01111101 Gyro2 0 630 deg s Validity 01111101 Gyro2 0 630 deg s Validity 01111101 Gyro2 0 630 deg s Validity OO000000 Gyro2 0 000 deg s Gyro 1 840 deg s Jown Acc 8 818 m s2 Gyro 1 730 deg s Down Acc 8 813 m s2 Gyro 1 730 deg s Down Acc 8 818 m s2 Gyro 1 840 deg s Down Acc 8 813 m s2 Gyro 1 730 deg s Down Acc 8 813 m s2 Gyro 1 840 deg s Down Acc 8 818 m s2 Gyro 1 730 deg s Down Acc 8 813 m s2 Gyro 1 730 deg s Down Acc 8 818 m s2 Gyro 1 730 deg s Down Acc 8 813 m s2 Gyro 1 730 deg s Down
7. well as the stored clock drift All GPS receiver parameters are also set back to the factory defaults Note When Cold start is selected all GPS receiver settings are reset to factory defaults with the exception of low power settings 3 When you selected the Warm Start Init reset mode enter or load the X Y and Z coordinates for the current position of the GPS receiver 4 Load a file containing the X Y Z coordinates by clicking Load The Specify a Name for the Position File window is displayed Specify a Name for the Position File x Look in Ca 336 EXE ee a8 SIRF POS File name Files of type Position Files pos Cancel ef FF PO ti 5 Select the sample sirf pos configuration file 3 38 SiRFDemo User Guide June 2007 Using the SiRFDemo Software Uo Hi Note An example file called sirf pos is provided with the SiRFDemo software See Modifying the Sample sirf pos File on page B 1 for more information on creating a valid pos file 6 Click Open The Receiver Initialization screen is displayed again 7 Enter 96 000 in the Clock field 96 000 is a typical clock drift value of the crystal in the GPS receiver Note When you enter zero in the Clock field the GPS receiver uses its last stored value or a default of 96 000 when no prior stored value is available 8 Click on or off the Use current PC time checkbox Note It is recommended that you
8. 1 Click the Map View button or select Map from the View menu The Map View screen 1s displayed 2101 Clear GPS Time 246597 51 Week 167 Lat 3737556 Hodo 134 Mode 3d Lon 121 91466 Yel 0 092 QOF 0 6 Fix Yalidated Alt 18 o 543 Used in Fis 10313281384271 The current position is represented on the plot by a red dot while past positions are displayed in blue 2 Click Clear at any time to clear any plotted positions on the plot 3 Click Current as Origin to make the origin of the plot the same as the most recent plotted position Note When using the map view you may want to change the way it is displayed To edit display preferences see Changing the Map View Preferences on page 3 13 Changing the Map View Preferences The ability to change the scale of the Map view and the origin of the map is provided by the Map view preferences To change the Map view preferences 1 Double click the Map View screen to display the Preferences window x View Cena meters pixel i Ring radii ca ZE a Origin Lat 37 37555 Lon E 21 91466 Using the SiRFDemo Software 3 13 3 14 2 Enter the number of meters you want each pixel to represent in the meters pixel field This value controls the map scale 3 Enter the latitude and longitude in WGS 84 of the required center of the Map View display in the Lat and Lon fields 4 To display up to three rings on the
9. A indicates product does not support map matching Flags indicate enabled disabled or true false map matching The PPS Timing View Screen The PPS Timing View screen reports the UTC time of the 1 PPS pulse whenever it has a current status from the satellites When the board does not have a valid UTC status it reports GPS time which is indicated by a status flag To display the PPS Timing View screen 1 Select Messages PPS Timing from the View menu SiRF Demo User Guide June 2007 Oo IH The PPS Timing View screen is displayed PPS Timing Yiew Time hh mm 22 00 02 49 Date ddmmyyyy 03 10 2003 UTC Offset sec 13 000000004 Status Time is valid true false True GPS Time or UTC Time UTC Time Reported UTC to GFS time info is current huerfalse True The following table provides a description of each of the displayed items Information Description Time hh mm ss The time of the 1 PPS pulse Date dd mm yyyy The date of the 1 PPS pulse UTC Offset sec The time offset from UTC Time is valid true false The validity of the displayed time GPS Time or UTC Time The time type being displayed UTC to GPS time info is current An indication of whether the information to convert from true false GPS to UTC time is valid Aux Output View Screen The Aux Output view screen displays messages when aux serial port message forwarding has been enabled To view the Aux Ouput view screen 1 Select Aux Output
10. Acc 8 818 m s2 Gyro 0 000 deg s Down Acc 0 000 m s2 Long Acc 0 548 m s2 Lat Acc 0 713 m s2 Long Acc 0 553 m s2 Lat Acc 0 709 m s2 Long Acc 0 548 m s2 Lat Acc 0 713 m s2 Long Acc 0 553 m s2 Lat Acc 0 709 m s2 Long Acc 0 553 m s2 Lat Acc 0 709 m s2 Long Acc 0 548 m s2 Lat Acc 0 713 m s2 Long Acc 0 548 m s2 Lat Acc 0 709 m s2 Long Acc 0 548 m s2 Lat Acc 0 713 m s2 Long Acc 0 548 m s2 Lat Acc 0 713 m s2 Long Acc 0 553 m s2 Lat Acc 0 709 m s2 Long Acc 0 000 m s2 Lat Acc 0 000 m s2 SiRFDRive 1 x Sensor Package of Valid Reverse Time Odo Spd Gyro Hdg Rte Time Odo Spd Gyro Hdg Rte Time Odo Spd Gyro Hdg Rte Time Odo Spd Gyro Hdg Rte Time Odo Spd Gyro Hdg Rte Time Odo Spd Gyro Hdg Rte Time Odo Spd Gyro Hdg Rte Time Odo Spd Gyro Hdg Rte Time Odo Spd Gyro Hdg Rte Time Odo Spd Gyro Hdg Rte Note The image above reflects the data fields present when SiRFDiRect is the target software SiRFDRive 1 x Sensor Package The following table provides a description of each of the displayed items for the SiRFDRive 1 x Sensor Package field Table 3 8 SiRFDRive 1 x Sensor Package Field Items Item Description Sensor Package of Valid Reverse Type of sensor package currently in use The number of valid measurements Reverse indicator SiRF Demo User Guide June 2007 Using the SiRFDemo Software Oo IH
11. Ephemeris By default SiRFDemo automatically detects the SiRF GPS product being used and is configured accordingly Throughout this manual where appropriate the product that a particular SIRFDemo feature supports is indicated 1 1 Hi Pana SiRF Demo Menus 1 2 The SiRFDemo software typically has six menus seven when SiRFDRive SiRFDiRect amp SiRFNav are selected as target software This seventh menu is also available when SiRFDRive is chosen as the target software All menus are described in Table 1 1 Table 1 1 SiRFDemo Menus Menu Description Setup View Action Navigation The Setup menu lets you configure the data source used by SiRFDemo and the operating preferences via these menu items Target Software Time Data Source Preferences Software Info See The Setup Menu on page 3 1 for detailed information about the Setup menu The View menu lets you display different view windows The available view windows include Signal Radar Map Navigation Response Output Error Debug DGPS Geodetic Nav PPS Timing Auxiliary Output SiRFDRive available only when the selected software target is SIRFDRive SiRFDiRect or SiRFDRive amp SiRFNav SiRFDRive Sensor available only when the selected software target is SiRFDRive SiRFDiRect or SiRFDRive amp SiRFNav SiRFDiREct Graph available only when the selected software target is SiRFDiRect Ephemeris Information available only w
12. MapView display enter the radius in meters of each of the rings in the Ring Radii group When a value of zero is entered the ring is not be displayed 5 Click Save to save the changes or Cancel to exit The Navigation Message View Screen The Navigation Message view screen is used to display position solution information such as GPS time GPS week position mode current position heading velocity DOP type of position fix and satellites tracked To view the Navigation Message View screen 1 Select Navigation Message from the View menu The Navigation Message View screen is displayed Navigation Yiew a 5 x Pa in Z Position m 2bo2o22 4307675 3050575 Velocity miz 0 000 0 000 0 000 Lat 37 37543 Lon 121 91467 Alt 12 Heading 0 Mode Sd GPS Week 313 DOP 1 600 Fix Validated Time 163990 00 54 used in fix 1317027 231638 Time To First Fix 17 1 sec Table 3 5 Navigation Message View Information Information Displayed Description X Y Z positions Coordinates of user s position in ECEF meters Velocity User s velocity in ECEF m sec Latitude User s latitude decimal of degrees Longitude User s longitude decimal of degrees Altitude User s altitude meters Heading GPS product s direction Mode Navigation solution type This changes from a No Nav status through the different fix modes such as 2D 3DLSQ etc The Mode field should be used for any TTFF measurement
13. O 731 339 1 114 524 60022901 7 08 NI 180674 NI 197510 156573 163591 178370 178371 240329 459834 468265 729697 0895599 1238485 2548853 3 754 672 and 1 316 228 Other United States and foreign patents are issued or pending SIRF SiRFstar SIRFLoc SIRFDRive SIRF XTrac and the SiRF logo are registered trademarks of SIRF Technology Inc SIRF Powered SnapLock FoliageLock TrickleP ower SingleS at SnapS tart Push to F ix SIRFNav SiRFstarll SiRFstarlll SIRFSoft SIRFFlash SIRFView SoftGPS Multimode Location Engine UrbanGPS SiRFLink and WinSiRF are trademarks of SIRF Technology Inc Other trademarks are property of their respective companies This document contains information about SIRF products SIRF reserves the right to make changes in its products specifications and other information at any time without notice SIRF assumes no liability or responsibility for any claims or damages arising from the use of this document or from the use of integrated circuits based on this data sheet including but not limited to claims or damages based on infringement of patents copyrights or other intellectual property rights No license either expressed or implied is granted to any intellectual property rights of SIRF SIRF makes no warranties either express or implied with respect to the information and specification contained in this document Performance characteristics listed in this document do not constitute a warranty or guarantee
14. Power Mask GPS satellites that have a low signal strength are not easily tracked by a GPS receiver and may result in using signals that are either noisy or have been effected by multipath or other interference source To increase accuracy it may be necessary to exclude GPS satellites with a signal strength below a selected value Note Not valid when operating in SiRFDRive mode To exclude satellites from the position solution with a signal strength below a selected value 1 Select Power Mask from the Navigation menu The Power Mask screen is displayed Power Mask Default x Set minimum satellite signal power to be required for l Cancel Navigation JEHz 28 2 Enter the minimum satellite signal level for satellites to be used in any position solution 3 Click Send to accept or Cancel to exit 3 60 SiRF Demo User Guide June 2007 Oo IH Enabling Disabling the Static Navigation The steady state detection allows the navigating algorithms to decrease the noise in the position output when the acceleration is below the threshold This reduces the position wander caused by Selective Availability SA and improves position accuracy especially in stationary applications To select the static navigation mode 1 Select Static Navigation from the Navigation menu The Static Navigation screen is displayed Static Navigation Default X ane UE Cancel 2 Select the option that you want to use
15. Table 3 8 SiRFDRive 1 x Sensor Package Field Items continued Item Description Time Sensor time in seconds does not correspond with GPS time Odo Speed Odometer speed Gyro Hdg Rte Gyro heading rate SiRFDRive 2 x and SiRF DikRect Sensor Packages The following tables provide a description of each of the displayed items for the SiRFDRive 2 x and SiRFDiRect Sensor Packages field Note The values displayed are dependent on the connected sensor package If using a SiRFDRive receiver SiRFDRive 2 x parameters will be displayed If using SiRFDiRect SiRFDiRect information will be shown The following table explains the SiRFDRive 2 x data fields Table 3 9 SiRFDRive 2 x Sensor Package Field Items Item Description Sensor Pkg Type of sensor package currently in use Sensor Data Type Type of data being output by sensor of Valid Number of valid measurements Reverse Reverse indicator Time Sensor time in seconds does not correspond with GPS time Validity Binary validity code Odo Speed Odometer speed RF Wheel Right front wheel speed data LF Wheel Left front wheel speed data RR Wheel Right rear wheel speed data LR Wheel Left rear wheel speed data The following table explains the SiRFDiRect data fields Table 3 10 SiRFDiRect Sensor Package Field Items Item Description Sensor Pkg Type of sensor package currently in use Sensor Data Type Type of data being output by sensor of Valid Number of valid measurements R
16. acquisition of GPS satellite signals The almanac is a subset of satellite ephemeris data and is updated weekly by GPS Control The almanacs for all 32 possible satellite PRN numbers are sent by the satellites in subframes 4 and 5 of the navigation message with one satellite almanac in a single subframe It takes 12 5 minutes for all satellite almanacs to be transmitted The vertical distance between a reference point and the receiver In GPS systems the altitude is always computed with respect to the WGS 84 reference ellipsoid q v However the receiver may contain a model that allows it to estimate the mean sea level MSL relationship to the reference ellipsoid and then report MSL altitude as well A technique that allows navigation using measurements from three GPS satellites plus an independently obtained value of altitude This permits computing a position solution with less than the normally required 4 satellites A navigation mode during which a value of altitude is processed by the Kalman Filter as if it were a range measurement from a satellite at the Earth s center WGS 84 reference ellipsoid center Bus Address Ball Grid Array The rate of change on a serial data line Often but not always the same as bits per second See bps Bill Of Materials Bits per second the rate of data transmission on a serial data bus In most cases this can be referred to as baud Celsius a unit of temperature Coarse Acquisition Code A
17. almanac file to a GPS receiver 1 Select Set Almanac from the Action menu The Specify Almanac Data Filename To Load screen is displayed Specify Almanac Data Filename To Load ajx Look in SiRFdemo 0 EE File name Jalmanac alm Files of type Almanac Files FZ alm Cancel Ki 2 Select the file you want to use 3 Click Open Note The almanac file must be in the same format as polled from a SiRF GPS receiver To download an almanac file from a GPS receiver see Downloading an Almanac File on page 3 67 Uploading an Ephemeris to a GPS Receiver An ephemeris 1s used by a GPS receiver to calculate the position of the satellites and hence the position of the GPS receiver When an ephemeris file is not available it must be downloaded from a GPS satellite To eliminate the time required to download this information from the GPS constellation a current ephemeris file can be uploaded to a GPS receiver using the SiRFDemo software To upload an ephemeris file to a GPS receiver 1 Select Set Ephemeris from the Action menu Using the SiRFDemo Software 3 47 IH Oo The Specify Ephemeris Data Filename To Load screen is displayed Specify Ephemeris Data Filename To Load x Look in O My Documents dm t c Ez My Received Files My Downloads P My Webs My eBooks _JMySetups C1 My Music CI My QukdoorNay Maps CA My Pictures File name ephemriz eph Files of type Ephem
18. beacon receiver is used to provide RTCM corrections No Beacon received from an operating radio beacon A beacon antenna is Receiver required 3 When the Internal DGPS Beacon Receiver is the chosen DGPS source select the auto scan options Auto Search Description Frequency The internal beacon receiver automatically scans the radio beacon frequency range until a usable signal is acquired When this option is deselected you must enter a signal frequency for the beacon receiver to use Bit Rate Radio beacons can broadcast the correction information using different bit rates the number of bits of data per second When this option is selected the internal beacon receiver also searches the different available bit rates until a usable signal 1s acquired When this option is deselected you must select a signal bit rate for the beacon receiver to use 4 Click Send to accept the settings Note The selection made in the DGPS Source screen is displayed in the DGPS Status View screen by selecting Messages DGPS Status from the View menu Setting the SBAS Operating Mode Using the SiRF Demo Software SBAS support can be configured using the SBAS configuration dialog To select the SBAS operation 1 Select SBAS Control from the Navigation menu The SBAS screen is displayed SBAS Default l x W AutoScan E l PEN Cancel Mode Timeout source Testing Default Integrity C User defined 3 63 IH O
19. connected communication port and the used Baud rate must be selected File SiRFDemo uses data that 1s contained within an existing data file The file may contain data in either SiRF Binary or NMEA formats Random SiRFDemo uses randomly generated data Use this option to verify that the SiRFDemo software is running without any receiver connected Aux Data Provided for SiRFDRive use only SIRFDemo can be configured to receive Source external data from another source other than the GPS receiver Note SiRFDemo only displays a list of available serial ports When USB is being used the USB port is listed as an additional serial port Using the SiRFDemo Software 3 3 3 4 3 Click OK to accept selected settings Aux Serial Port Message Forwarding When both the Main and Aux serial ports are open some SiRF Binary messages received on one port are forwarded to the other port To use the auxiliary data source 1 Select Data Source from the Setup menu The Data Source Setup screen is disrplayed Data Source Setup Serial Port COM1 Baud Rate 57600 Cancel C Random Virtual Serial Port Data Piping Create Virtual Serial Port Port Protocol Aux Data Source lv Use Aux Data Source Por COMG Baud Rate 115200 v 2 Check the Use Aux Data Source checkbox Any SiRF Binary message received on the Aux port is sent to the Main port and logged in the gps log file as CLM gt GPS Whe
20. data of SiRFdemo GPS Time Px Py Pz DOP Model Mode2 SVs used Thru put SV tracked x vel is the time tagged position file in ECEF Vx Vy Vz parsed from record 002 measured navigation data of SiRFdemo GPS Time Vx Vy Vz DOP Model Mode2 SVs used Thru put SV tracked is the satellite specific data for each Sv tracked where is the Sv prn number This data is parsed form record 004 measured tracker data from SiRFdemo 1 e Satellite data for Sv Number 22 will be in file 4 022 GPS Time AZ El Avg C No 256707 11 297 35 44 256708 11 297 35 45 256709 11 297 35 45 x svs contains statistics that are generated each time the program processes a data file on a per satellite basis Statistical data file svs Statistical data per Sv based on file Sv Mean Std Dev Max Min Range Data SiRFDemo Users Guide June 2007 2 D 3 D A D AGC Almanac Altitude Altitude Hold Altitude Hold Mode BA BGA Baud BOM bps C C A Code SiRFDemo User Guide June 2007 Acronyms and Abbreviations Glossary A IH Two dimensional Three dimensional Analog to Digital Automatic Gain Control A set of orbital parameters that allows calculation of the approximate GPS satellite positions and velocities A GPS receiver uses the almanac as an aid to determine satellite visibility during
21. is displayed Receiver initialization Cancel Penodic reset 0 5 or more si E Ca a MU M Ha paaa i Reset mode Messages Snap Start i Enable Nav Lib Data Hot Start kW Enable Debug Data Warm Start No init warm Start Init W Clear User Data in Cold Start Battery Backed RAM Factory Reset 3 37 IH Oo 2 Select type of Reset Mode by clicking the associated radio button Description Snap Start Hot Start Warm Start No Init Warm Start Init Cold Start Factory Start The GPS receiver restarts by using the values stored in the internal memory of the GPS receiver The following validated parameters are used time position almanac and ephemeris The GPS receiver restarts by using the values stored in the internal memory of the GPS receiver validated ephemeris and almanac This option has the same functionality as Hot Start except that it clears the ephemeris data and retains all other data This option clears all initialization data in the GPS receiver and subsequently reloads the data that is currently displayed in the Receiver Initialization Setup screen The almanac is retained but the ephemeris is cleared This option clears all data that is currently stored in the internal memory of the GPS receiver including position almanac ephemeris and time The stored clock drift however is retained This option clears all data including position almanac ephemeris time as
22. less the errors in the position solution Related indicators include PDOP HDOP TDOP and VDOP Greenwich Mean Time now commonly called Universal Coordinated Time or UTC The Navstar Global Positioning System A space based radio positioning system that provides suitably equipped users with accurate position velocity and time data GPS provides this data free of direct user charge worldwide continuously and under all weather conditions The GPS constellation consists of 24 or more orbiting satellites spaced around each of six different orbital planes The system is developed by the DoD under Air Force management The number of seconds since Saturday Sunday Midnight with time zero being this midnight Used with GPS Week Number to determine a specific point in GPS time GPS time is related to UTC but differs from it by an integer number of leap seconds and by a variable time that is normally controlled to be less than 20 ns Graphic User Interface Horizontal Dilution of Precision A measure of how much the geometry of the satellites affect the position estimate computed from the satellite range measurements in the horizontal East North plane The altitude value that is sent to the Kalman filter as a measurement when in Altitude Hold Mode A startup mode for a GPS receiver in which the receiver knows the approximate time its approximate position and in which it has sufficient ephemerides in its memory so that once it acquires the
23. may also be used for mission planning and constellation investigations To download an almanac file 1 Select Almanac from the Poll menu The Specify Almanac Data Filename To Save screen is displayed Specify Almanac Data Filename To Save x Save In SiRFdemo do fl pi EE File name Jalmanac Save as lupe Almanac Files 2 alm Cancel 2 Specify the file name in which to save the almanac information Ki 3 Click Save to save the data to file A message box 1s displayed to confirm completion To load an almanac file see Uploading an Almanac to a GPS Receiver on page 3 47 3 67 3 68 Downloading an Ephemeris File You can download an ephemeris file from a SiRF GPS receiver and load it back into the receiver at a later date or to another GPS receiver This is to assist with initial position calculations This file may also be used for mission planning and constellation investigations The downloaded ephemeris which contains information on the status of each satellite could have been acquired from a broadcast ephemeris an extended ephemeris or a combination of both depending on what SiRF GPS product was being used To download an ephemeris file 1 Select Ephemeris from the Poll menu The Specify Ephemeris Data Filename To Save screen is displayed Specify Ephemeris Data Filename To Save x Save In SiRFdemo do fl EF BN File name ephemris Save as type E phemeris Files eph
24. of product performance SIRF products are not intended for use in life support systems or for life saving applications All terms and conditions of sale are governed by the SIRF Terms and Conditions of Sale a copy of which may obtain from your authorized SIRF sales representative J une 2007 DI Please amp O Recycle
25. or licensed by SIRF Technology Inc are protected by one or more of the following United States patents 5 148 452 5 175 557 5 436 840 5 488 378 5 504 482 5 552 794 5 592 382 5 638 077 5 663 735 5 745 741 5 883 595 5 897 605 5 901 171 5 917 383 5 920 283 6 018 704 6 037 900 6 041 280 6 044 105 6 047 017 6 081 228 6 114 992 6 121 923 6 125 325 6 198 765 6 236 937 6 249 542 6 278 403 6 282 231 6 292 749 6 295 024 6 297 771 6 300 899 6 301 545 6 304 216 6 351 486 6 351 711 6 366 250 6 389 291 6 393 046 6 400 753 6 421 609 6 427 120 6 427 121 6 448 925 6 453 238 6 462 708 6 466 161 6 466 612 6 480 150 6 496 145 6 512 479 6 519 277 6 519 466 6 522 682 6 525 687 6 525 688 6 526 322 6 529 829 6 531 982 6 532 251 6 535 163 6 539 304 6 542 116 6 542 823 6 574 558 6 577 271 6 583 758 6 593 897 6 597 988 6 606 349 6 611 757 6 618 670 6 633 814 6 636 178 6 643 587 6 646 595 6 650 879 6 662 107 6 665 612 6 671 620 6 675 003 6 680 695 6 680 703 6 684 158 6 691 066 6 703 971 6 707 423 6 707 843 6 714 158 6 724 342 6 724 811 6 738 013 6 747 596 6 748 015 6 757 324 6 757 610 6 760 364 6 775 319 6 778 136 6 788 655 6 788 735 6 804 290 6 836 241 6 839 020 6 850 557 6 853 338 6 856 794 6 885 940 6 888 497 6 900 758 6 915 208 6 917 331 6 917 644 6 930 634 6 931 055 6 931 233 6 933 886 6 950 058 6 952 440 6 961 019 6 961 660 6 985 811 7 002 514 7 002 516 69714581 6
26. sleep mode until it is reawakened by the RTC generated wake up interrupt The default parameter values are Update Rate 1 second On Time 200 ms 3 51 3 52 Maximum Off Time 30 000 ms Maximum Search Time 120 000 ms Adaptive TricklePower An Adaptive TricklePower option is also available Adaptive TricklePower is a feature of the software that allows the receiver to operate in TricklePower when possible but then switch to full power when difficult environments are encountered Once the operating environment improves the receiver returns to TricklePower mode This function results in improved navigation performance in difficult environments while still minimizing power use in good operating environments Push to Fix For applications where a position fix is required on demand that is not continuous the Push to Fix mode is the most appropriate mode of operation for power sensitive situations In this mode the receiver turns on periodically according to the user specified parameter Push To Fix Period When the receiver turns on the ephemeris records are updated and the clocks calibrated When all internal updating tasks are complete the receiver powers itself off except for RTC and schedules the next wake up period The default parameter is Push To Fix Period 1 800 seconds When the GPS receiver is power cycled externally a navigation solution is be available to the user in three seconds To set
27. spread spectrum direct sequence code applied to the GPS satellite carrier signal This code is typically the only one used by commercial GPS receivers to compute the range between receiver and the satellite Military receivers use this code only to acquire the satellite signal and then typically switch to the P code for more precise ranging C 1 Clock Error CMOS CINg Cold Start Control Segment AB dBiC dBm dBW DC DGPS Doppler Aiding DoD DOP DRAM DSP DTR ECEF EA EEPROM EHPE EMC EMI EPE C 2 Circular Error Probable The radius of a circle centered at the user s true location that contains 50 percent of the individual horizontal position measurements made using a particular navigation system The uncompensated difference between synchronous GPS system time and time best known within the GPS receiver Also called Clock Error Complimentary Metal Oxide Semiconductor Carrier to Noise density ratio In spread spectrum systems like GPS this is equivalent to signal to noise ratio in a conventional radio system A startup condition in a GPS receiver in which the receiver does not have position time or both and in which it does not have ephemeris In this type of a start it must search for satellites without knowing which ones may be visible and once it finds satellites it must learn their ephemeris by listening to the navigation message of each satellite The Master Control Station and the global
28. the GPS receiver to TricklePower mode 1 Select Set TricklePower Parameters from the Action menu The Low Power screen is displayed x C Continuous Cancel f TricklePower C Push To Fix Adaptive mode Invalid setting J Update rate zec fi On time ma 200 00 900 Maximum off time mg j30000 Maximum search time mg 120000 Eush io tie penad leechi Mal 2 Select the required operating mode SiRFDemo User Guide June 2007 3 3 When TricklePower is selected select the Update Rate and On Time from the dropdown menu and enter the Maximum Off Time and Maximum Search Time 4 Select the Adaptive mode checkbox when Adaptive TricklePower operation is required 5 Click Send to activate selection Table 3 14 shows the Update Rate and On Time combinations that the GPS receiver supports when in TricklePower Table 3 14 TricklePower Update Rate and On Time Update Rates seconds On Time ms 5 6 p 200 300 400 500 600 YARA 3f Sf ON 700 800 900 RU Ba ka SIS Apn So Ne Wu ni SS Aalsa Nail NG NB Se SSS SN SN NS SSS SN SN NS S SN SN SN SN SNN SN a Kal Na Bal Kal Kal NG KN NE Ni NB Ni No Tol ul SS XE NE NEN SN SN NS To conserve power at start up you can control how long Maximum Search Time the system should attempt to acquire satellites and navigate and how long
29. the target software See The SiRFDRive Menu on page 3 69 for detailed information about the Poll menu Note The values that appear in the dialog boxes are default values and not what is currently set in the GPS receiver See Polling the Navigation Parameters on page 3 66 to determine the current settings of all navigation parameters 1 3 Getting Started 2 This chapter describes the minimum computer requirements installing SIRFDemo and how to quickly get started using the software See Chapter 3 Using the SiRFDemo Software for detailed information on SiRFdemo operation Computer Requirements The following is the minimum computer configuration that is required to achieve reliable operation 486 processor or better e 16MB RAM minimum memory e 100MB minimum available disk space for PC software tools installation and data logging Windows 98 NT 2000 or XP operating system One available RS232 serial port Installing SiRF Demo To install SiRFDemo from the provided CD 1 Insert the CD into your CD ROM drive A CD browser automatically launches and displays on the screen 2 Select Install Software Tools from the main menu of the browser interface 3 Select SIRFDemo An install shield guides you through the rest of the installation SiRF Demo User Guide June 2007 2 1 IH KO Installing USB Drivers 2 2 i SiRFDemo InstallShield Wizard SiIRFDemo After installation is com
30. they are preserved over hot and warm software resets but revert to default values over power cycles cold and factory resets Transmitting a User Defined Serial Message Using the SiRF Demo Software The Transmit Serial Message function provides the ability for a user to send generic serial messages to the attached target platform The message can be automatically wrapped with SiRF Binary or NMEA information or transmitted as is To transmit a user defined message to the target platform 1 Select Transmit Serial Message from the Action menu The Send Data screen is displayed Send Data Specify in Hex e g 55 AB GO However use text format for NMEA and None ASCII Cancel Protocol Wrapper cE re Ce SiRF Binary ee maa C NMEA G cdalab ckirin None HEX C Hone ASCII Send To Aux Data Source 3 55 IH Oo The Navigation Menu 3 56 2 Enter the payload of the message that you want to send to the target platform in the text field Use Hex format for a binary message content or ASCII for intended NMEA messages Note The defined message can be saved in a cmd file by clicking Save and specifying a file name A previously defined message that was saved can be loaded by clicking Load and selecting the appropriate file 3 Select the desired protocol wrapper from the Protocol Wrapper options Description Default SiRF Binary The payload of the message is converted to binary with On t
31. to the plane of the user direction Voltage Standing Wave Ratio Start mode of the GPS receiver when current position clock offset and approximate GPS time are available in the receiver but no current ephemeris is available In a warm start the receiver has sufficient information to predict which satellites are visible but once these satellites are acquired the receiver must learn their ephemerides by listening to their navigation messages World Geodetic System 1984 A mathematical ellipsoid designed to fit the shape of the entire Earth It is often used as a reference on a worldwide basis while other ellipsoids are used locally to provide a better fit to Earth in a local region GPS uses the center of the WGS 84 ellipsoid as the center of the GPS ECEF reference frame and the surface of the reference ellipsoid as the basis of latitude longitude and ellipsoidal altitudes C 7 C 8 SiRFDemo User Guide June 2007 SIRF Sales Offices SiRF North America SiRF Europe SiRF Asia Pacific Corporate Headquarters Germany India 1 408 467 0410 49 81 529932 90 91 120 251 0256 sales sirf com salesgermany sirf com salesindia sirf com www sirf com France Taiwan 33 6 071 7 1862 886 2 8789 6566 salesfrance sirf com salesasiapacific sirf com United Kingdom Japan 44 1344 668390 4 81 44 829 2186 salesuk sirf com salesjapan sirf com SiRFDemo User Guide Copyright 1996 2007 SIRF Technology Inc All rights reserved Products made sold
32. use PC time it 1s assumed that the date and time on your computer are set correctly 9 When you select Use current PC time enter the UTC offset for your location in the UTC offset field 10 When you do not select Use current PC time enter the number of the week and the time of the week in the corresponding fields 11 Enter the number of channels in the Channel field You can specify from 1 to 12 channels 12 Check Enable Nav Lib Data to log navigation library data 13 Check Enable Development Data to turn on message 255 The content of this message is displayed in the Development Data View The Baud rate of the SiRFDemo software and the attached GPS receiver is automatically changed to 57600 to ensure sufficient through put to accommodate the quantity of data Note The Development Data output by a GPS receiver is required to assist in the analysis and debug of system performance problems It is highly recommended to enable Development Data during development and testing in the event that support is needed from SiRF 14 Enter a periodic reset value in the Periodic Reset field to automatically reset the board at the defined interval Valid values are 5 to 600 seconds A value of zero cancels the periodic reset function 15 Check Clear User Data in Battery Backed RAM to force user defined data to be reset to their default values 16 Click Send to initialize or Cancel to exit 3 39 3 40 ka When SiRFNav amp SiR
33. Calibrating the Gyro on page 3 70 Setting DR Sensor Parameters on page 3 71 e Polling Gyro Factory Calibration on page 3 72 e Polling DR Sensor s Parameters on page 3 72 Note The SiRFDRive menu is only available when SiRFDrive SiRFDiRect or SiRFNav amp SiRFDRive is selected as the target software Not all functions are available for all softwares 3 69 IH Oo Setting Navigation Mode Control To set the SiRFDRive navigation mode control 1 Select SiIRFDRive Navigation Mode Control from the Navigation menu The SiRFDRive Navigation Mode Control screen is displayed GPS Nay Only C DA Nay Orly C DR Nav Ok w stored or default calibration C DRA Nav Ok w current GPS calibration 2 Select the radio button for a SiRFDRive Navigation Mode Description GPS Nav Only User can configure the device to use GPS navigation only DR sensors are not used for navigation DR Nav Only Dead reckoning navigation is used exclusively GPS updates are received but not used for navigation DR Nav Ok w stored or DR navigation can be specified at startup by using DR sensor default calibration calibration stored in RAM 1 e OK to do DR only at startup when no update from GPS is available This is the default navigation mode at startup DR Nav OK w current DR Navigation must use current GPS based calibration i e no DR GPS calibration Navigation after startup until after calibration by GPS 3 Cli
34. Clock Bias Number of continuous weeks that GPS has been operational The start date being January 6 1980 Time of Week the number of GPS seconds since the start of the current GPS week The start of the GPS week being O hrs Sunday UTC Estimated TOW while the GPS receiver is not tracking GPS satellites Number of satellites currently being tracked and used in the position solution Change in the clock bias A typical range is between 76kHz and 116kHz Offset of the GPS receiver clock compared with the current GPS time 3 65 3 66 Polling the Navigation Parameters All of the user settings that have been set under the Action and Navigation menus can be polled for their current status and settings To poll a GPS receiver for its current navigation parameters 1 Select Navigation Parameters from the Poll menu The current settings are displayed in the Response View window Response View E GC Eg Hy Acknowledged MID PollReMgrPararns AltMode auto E AlS ource last KF alt Altitude 0 DegradedMode TThenD Degraded timeout 30 DR Timeouk 15 3 TrkSmoothMode enabled Statichay enabled 35 L50 enabled DOPMaskMode disabled Elevtdask 7 5 deg Pwd ask 28 dBHz DGPS 5 re Seral DGP5S Mode auto DGPS Timeout 30 Continuous power enabled User tasks disabled bdawacgT ime 0 ms MaxDOffT ime 0 mg A description of each of the navigation parameters are given in the following table Table 3 16 Navi
35. FDRive is selected as the target software the SIRFDRive Navigation Initialization option is available instead of Receiver Initialization You can reset or initialize a GPS receiver directly through the SiRFDemo software This function may be used to demonstrate or evaluate the Board s recovery ability under different circumstances The SiRFDrive Navigation Initialization enables you to specify location and heading after a Warm w Init reset This data aids in acquiring the first fix Initializing SURFDRive Navigation Parameters 1 Click the reset button or select SiRFDRive Navigation Initialization from the Navigation menu The SiRFDRive Navigation Initialization screen is displayed SiRFDRive Navigation Init X Latitude deg E Longitude deg aa Cancel Altitude fram ellipsoid mk True heading deg oO Clock offset Hal UTC offset 8 Week number Time of week s Channels Reset mode Messages Snap W Mav Lib e Hot i Debug C Warm Co Warm v Init i Clear User Data in Cold Battery Backed RAM C Factor reset Select type of Reset mode by clicking the associated radio button The following table describes the reset types Table 3 13 Reset Options Reset Mode Description Hot GPS receiver restarts by using values stored in internal memory of the board The stored ephemeris and almanac are valid Warm Same functionality as Hot Start except that it clears the ephemeris data a
36. Hold Navigation Mode in which a fixed value of altitude is used for one or more position calculations while horizontal 2 D position can vary freely based on satellite range measurements Universal Asynchronous Receiver Transmitter adevice that produces an electrical signal and timing for transmission of data over a serial communications path and circuitry for detection and capture of such data transmitted from another UART User Differential Range Error A one sigma estimate of the pseudorange measurement error due to ambient noise and residual multipath User Equivalent Range Error an estimate of the pseudorange measurement error due to such system parameters as satellite clock and ephemeris error and ionospheric model errors The GPS receiver specification that indicates the solution rate provided by the receiver when operating normally Common update rates are once per second twice per second and 10 times per second Universal Coordinated Time This time system uses the second defined true angular rotation of the Earth measured as if the Earth rotated about its Conventional Terrestrial Pole However UTC is only adjusted in increments of one second The time zone of UTC is that of Greenwich Mean Time GMT Voltage Controlled Oscillator Vertical Dilution of Precision A measure of how much the geometry of the satellites affects the position estimate computed from the satellite range measurements in the vertical perpendicular
37. Maximum Off Time the GPS receiver should remain off sleep mode before making another attempt to navigate Maximum times are in ms Example Scenario 1 Result Scenario 2 Result Scenario 3 Result Using the SiRFDemo Software Maximum Off Time 30000 ms default Maximum Search Time 300000 ms default System is turned on but does not acquire Svs no antenna connected System searches for 120000 ms sleeps for 30000 ms searches again for 120000 ms etc System is turned on and acquires Svs but does not navigate System searches for 120000 ms sleeps for 30000 ms searches again for 120000 ms etc System is turned on acquires and navigates Sleep mode is disabled 3 53 3 54 Setting Advanced Power Management Options for SiRFX Trac When using SiRFXTrac the Advanced Power Management APM mode can be enabled or disabled When the APM mode is enabled settings for accuracy and timing plus many other power management options are available To view the SiRFXTrac APM settings 1 Select Set Advanced Power Management APM from the Action Menu The XTrac APM screen is displayed Low Power XTrac APM Mode Ce APM Disable Continuous Mode Ct APM Enable Power Saving Mode Num 4PM Cycles Before Sleep 0 455 0 cycles means unlimited APM cycles APM Settings Time Between Fires 10 180 sec Power Duty Cycle Timing Priority Preference a M Accuracy amp Timing Max Respo
38. Pause Display 30 BF Initialize Data Source 10 BF switch to NMEA Protocol 6 BF Switch bo SIRF Protocol Synchronize Protocol amp Baud Rate Switch ko Useri Protocol 2 BF Set Main Serial Port Set DGPS Serial Port 29 BF Set UART Configuration 15 BF Set Almanac 26 BF Set Ephemeris 15 BF witch Operating Mode Jit Spee Cl i r 16 BF Switch Gaaex SW Config Disable Broadcast Ephemeris Selecting this dropdown menu option sends msgID OxE8 subID OxFF with debug flags data 0x01000000 A broadcast ephemeris can also be disabled by checking the Disable Broadcast Eph checkbox in the Receiver Initialization screen by selecting Action Menu Initialize Data Source This sends msg OxE8 subId OxFF every second to the main serial port until the Ack message 0x38 OxFF is received Note The Ephemeris Info screen shows whether SiRFDemo is still sending the disable broadcast eph msg See also Ephemeris Information on page 3 29 SiRF Demo User Guide June 2007 Oo ll Setting Low Power Parameters Using the SiRFDemo Software Note Not valid when operating in SiRFDRive mode The GPS receiver can operate in three modes Mode Description Full Power Full power mode is the standard operating mode Power is supplied to the receiver continuously and the GPS receiver continues to operate without an interrupt TricklePower In TricklePower mode the power to the SiRF chipset is cycle
39. Rear axle heading rate error The following table provides a description of each of the displayed items for the DR NAV SUBSYSTEM DATA field Item Gps Hdg Rte Gps Hdg Rte Error Gps Hdg T Gps Hdg T Error Gps Spd Gps Spd Error Gps Pos Error DR Hdg Rte DR Hdg Rte Error DR Hdg T DR Hdg T Error DR Spd DR Spd Error DR Pos Error Using the SiRF Demo Software Description Rate of change in heading based on GPS solutions in degrees second Estimated error of the GPS heading rate in degrees second Heading from true north based on GPS solutions in degrees Estimated error of the GPS heading in degrees Speed over ground based on GPS solutions in meters second Estimated error of the GPS speed in meters second Estimated error of the last GPS position in meters Rate of change in heading based on DR sensor solutions in degrees second Estimated error of DR sensor heading rate in degrees second Heading from true north based on DR sensors in degrees Estimated error of DR sensor in degrees Speed over ground based on DR sensor solutions in meters second Estimated error of DR sensor speed in meters second Estimated error of the last DR position solution in meters 3 25 3 26 SIRFDRive Sensor View Screen The SiRFDRive Sensor view is only available when SiRFDRive is selected as the target software The SiRFDRive Sensor View screen provides detailed information output from the sensor package
40. Set Defaults Baud rate 9600 w Mate The User message rate settings will only apply if the User has created new NMEA Output messages using the j w SOK User 3 outputs FGPEZDA by default W Use checksums 2 Select the NMEA Messages by clicking the required message Option Description GGA GLL GSA GSV RMC VTG MSs Time position and fix related data for a GPS board receiver Latitude and longitude of present position time of position fix and status GPS board receiver operating mode satellites used in the position solution and DOP values The number of GPS satellites in view satellite ID numbers elevation azimuth and SNR values Time date position course and speed data provided by the GPS board receiver The actual course and speed relative to the ground Signal to noise ratio signal strength frequency and bit rate from a radio beacon receiver SiRF Demo User Guide June 2007 Uo Hi Option Description User 8 Reserved for a user defined NMEA string User 9 Reserved for a user defined NMEA string User 10 Reserved for a user defined NMEA string 1 When the attached GPS receiver does not support an internal beacon receiver the content of the MSS messages are not available 3 Select the update rate for each NMEA message from the corresponding Update Rate dropdown menu Each NMEA message can be output at a maximum rate of one per second and at a minimu
41. TA DWS SPeed SF Upd Gps Hdg Rte Error Gps Hdg T Error Gps Spd Error Gps Pos Error DR Hdg Rte Error DR Hdg T Error DR Spd Error DR Pos Error DR NAV STATUS The following table provides a description of each of the displayed items for the DR NAV STATUS field Table 3 7 NAV STATUS Field Items Item Description DR Nav Status of the DR navigation solution DR Data Status of the DR data being generated DR Cal Calibration status of the DR sensors DR Pos DR position status SiRFDemo User Guide June 2007 Uo Hi Table 3 7 NAV STATUS Field Items continued Item DR Hdg DR Nav across Reset DR Nav St Int Ran DR Nav State Upd Gps Pos Upd Gps Hdg Upd Gps Pos for DR GPS Vel for DR Gyro Subsys Op Odo Speed Subsys Op Gyro Bias Cal 0 Spd Gyro Bias Cal Upd Gyro SF Cal Gyro Bias amp SF Cal Upd Odo Speed SF Cal Odo Speed Cal Upd DWS Hdg Rate SF Cal DWS Hdg Rate SF Upd DWS Speed SF Cal DWS Speed SF Upd Description DR heading status Conditions are appropriate to do a DR navigation after a system reset or power cycle The DR navigation algorithm integrate the raw DR data Indicates whether the DR has updated the navigation state The GPS solution updated the navigation position during the cycle The GPS solution updated the heading during the cycle GPS position valid for DR GPS velocity valid for DR Operational status of the gyro heading sensor Operational status o
42. The speed computed from the DR portion of the solution in meters second Error in the DR speed in meters second Scale factor of the speed calibration Error in the DR speed scale factor The change in heading computed from the DR portion of the solution in degrees second Error in the DR heading rate in degrees second DR heading rate scale factor DR heading rate scale factor error DR sensor heading in degrees DR direction Total DR heading error Total DR position error Type of sensor package currently in use The bias or offset in the gyro heading sensor output in degrees second Error in the DR gyro bias in degrees second Odometer speed Odometer speed scale factor Left front wheel speed scale factor Left front wheel speed scale factor error Right front wheel speed scale factor Right front wheel speed scale factor error Left rear wheel speed scale factor Left rear wheel speed scale factor error Right rear wheel speed scale factor Right rear wheel speed scale factor error Front axle speed delta Front axle average speed Front axle average speed error SiRF Demo User Guide June 2007 F Axle Hdg Rte F Axle Hdg Rte Error R Axle Spd Delta R Axle Avg Spd R Axle Avg Spd Error R Axle Hdg Rte R Axle Hdg Rte Error DR NAV SUBSYSTEM DATA Oo Hi Front axle heading rate Front axle heading rate error Rear axle speed delta Rear axle average speed Rear axle average speed error Rear axle heading rate
43. able Status Clear Send Disable Broadcast Eph every 1 second until Ack is Revd SLEBF Binary Msg 56 SubID 1 Client Request Ephemeris from CLM Bequest Eph Time Since Last Peguest Eph Clear SLEF Binary Msg 30 SIRF Binary Msg 56 SubID 3 Poll Eph Pep Eph Clear Poll Eph Week TOE Inteq Aye Clear SU 01 SY 01 SUV OZ SU OZ SU 03 SUV 03 SU O4 SU 04 SY OG BY os SY 06 SU 06 SU 07 SU 07 SU 08 SU Os SY 03 BY 09 SU 10 SU 10 SU 11 SU 11 SU le 5y lz SU 13 SU l3 SU l4 SU l4 SU 15 SG SU 16 57 l SU 17 SW 17 SU 1s 5y l8 SY 19 5y 19 Sy z0 SW Z0 SU Z1 SW Zl Si Sa ee Sia SA SY Z4 SW 4 Si z5 SW 25 SY Z6 SW Z6 5y maat Bb SU A27 5y z6 SUOT Si z9 SW Z9 SU 30 SW 30 SU 31 Sy 31 SU 32 SM eee There are four sections in the Ephemeris View window when the disable broadcast eph message is received while the Ephemeris Info window is open Otherwise this section displays Status The Ephemeris Info View is only available when GSW 2 3 or newer is selected as the target software in the Setup menu 1 The first section displays the message Status Disable Broadcast Eph ACK rcvd 3 29 3 30 Disable sends msg OxE8 subID OxFF with debug flags data 0x01000000 this is the same as selecting Action Disable Broadcast Eph from the dropdown menus Clear resets the display message to Disable Broadcast Eph When the checkbox Send Disable Broadcast Eph every 1 second un
44. ards for marine communications Special Committee 104 of the RTCM established and maintains a communications protocol that is used in GPS receivers to send DGPS corrections between reference receivers and receivers using the corrections Selective Availability The method used by the DoD to control access to the full accuracy achievable with the C A code In May 2000 the DoD elected to turn SA off and may not use it again The angle of the satellite above the horizon Spherical Error Probable The radius of a sphere centered at the user s true location that contains 50 percent of the individual 3 D position measurements made using a particular navigation system A GPS receiver in which the number of satellite signals to be tracked exceeds the number of available hardware channels Sequential receivers periodically reassign hardware channels to particular satellite signals in a predetermined sequence Signal to Noise Ratio often expressed in decibels Serial Peripheral Interface a synchronous serial channel Standard Positioning Service A position service available to all GPS users on a continuous worldwide basis with no direct charge SPS uses the C A code to provide a minimum dynamic and static positioning capability Static Random Access Memory A form of RAM that maintains its contents as long as power is supplied without the need for periodic refreshing See DRAM Synchronous Serial Port Space Vehicle the common abbreviat
45. ates have the Z axis aligned with the Earth s spin axis the X axis through the intersection of the Prime Meridian and the equator and the Y axis is rotated 90 degrees East of the X axis External Address Electrically Erasable Programmable Read Only Memory Estimated Horizontal Position Error Electromagnetic Compatibility Electromagnetic Interference Estimated Position Error SiRF Demo User Guide June 2007 Ephemeris EPROM ESD EVPE FP FRP FSM GaAs GDOP GMT GPS GPS Time GUI HDOP Held Altitude Hot Start VO IF IRQ ISR IGRF IODC Acronyms and Abbreviations Glossary A set of satellite orbital parameters used by a GPS receiver to calculate precise GPS satellite positions and velocities The ephemeris of a satellite is broadcast by that satellite in subframes 1 2 and 3 of the navigation message It takes 18 seconds to transmit and is repeated every 30 seconds Erasable Programmable Read Only Memory Electrostatic Discharge Estimated Vertical Position Error Floating Point mathematics as opposed to integer Federal Radionavigation Plan The U S Government document that contains the official policy on the commercial use of GPS Finite State Machine Gallium Arsenide a semiconductor material Geometric Dilution of Precision A factor used to describe the effect of the satellite geometry on the position and time accuracy of the GPS receiver solution The lower the value of the GDOP parameter the
46. avigation Message Yiew OF x A YT Fa Position m 686541 4304311 3851688 Yelocity m 0 250 0 375 0 125 Lat 37 38735 Lon 121 97327 Alt 83 Hode Full 3D GPS Week 957 DOP 4 4 Fix Validated Time 346168 00 5 S s Used in Fix 21 23 317 22 SiRFDemo Users Guide June 2007 B 3 Modify the X Y Z positions in the sirf pos file with the new configuration values displayed on the Measured Navigation Message View screen 4 090721 4310924 204 L04 O Description of SiRF sig File Formats B 2 avg File The SiRFsig software produces the following files for plotting and statistics ares AS DOG vel FEF SVS Following are descriptions of each type of file x avg is the average data file used to calculate statistics It is created during parsing and used if data is reviewed without re parsing the data file Format Lines 0 32 are satellite data All fields are O if Sv is not tracked Sv Avg C No Number of Seconds Tracked 0 00 0 0 0 00 0 SiRF Demo Users Guide June 2007 File Formats ee Hi Bin Data for Polar Plots Bins are in a matrix of 8 8 with each bin defined by an azimuth range and elevation range Bin 0 0 is AZ 0 45 and El 0 10 degrees Bin 0 1 is Az 0 45 El 10 20 degrees Bin azimuths are in steps of 45 degrees in a clockwise direction elevation bins are in 10 degree steps starting at the horizon O degre
47. ck Send to accept the setting Calibrating the Gyro The factory calibration procedure requires that the Start Gyro Bias Calibration be done first while the gyro is stationary and then the Gyro Scale Factor Calibration be done while the gyro rotates smoothly through 360 degrees Note This function is not available in SiRFDiRect To start the gyro calibration 1 Select SiRFDrive Poll Gyro Factory Calibration from the Navigation menu 2 Select SiRFDrive Gyro Factory Calibration from the Navigation menu The SiRFDRive Gyro Factory Calibration Control screen is displayed 3 70 SiRF Demo User Guide June 2007 Uo Hi 3 Check the Start gyro bias calibration checkbox 4 Click Send 5 Wait for the Gyro Bias Calibration Finished message in the Response View 6 Select SiRFDrive Gyro Factory Calibration from the Navigation menu 7 Check the Start gyro scale factor calibration checkbox 8 Click Send 9 Rotate Gyro through exactly 360 degrees using highest possible angular rate or at least 40 deg sec 10 Wait for the Gyro Scale Factor Calibration Finished message in the Response View Setting DR Sensor Parameters To enter the following DR sensor parameters Speed scale factor meters per wheel tick Gyro Bias zero rate volt Gyro Scale Factor mV deg sec Note This function is not available in SiRFDiRect 1 Select SiRFDrive DR Sensor s Parameters from the Navigation
48. ctory where the drivers are located and press OK The drivers were copied to the SiRFDemo directory during the SiRFDemo installation By default the directory is C Program Files SiRF SiRFDemo usbDrivers Press Finish to complete the installation of the CP2101 USB Composite Device Windows now opens a second Found New Hardware Wizard window Repeat steps 2 through to 4 Press Finish to complete the installation of the CP2101 USB to UART Bridge Controller Windows 2000 Installation To install the required USB drivers on Windows 2000 l Getting Started Connect the USB enabled SIRF GPS receiver to your PC Windows opens a Found New Hardware Wizard window Press Next to continue Select Search for the best driver for your device Recommended and press Next Select Specify a location and press Next Press Browse and locate the file slabbus inf The drivers were copied to the SiRFDemo directory during the SiRFDemo installation By default the directory is C Program Files SiRF SiRFDemo usbDrivers Press Finish to complete the installation of the CP2101 USB Composite Device Windows now opens a second Found New Hardware Wizard window Press Next to continue and follow steps 2 through to 4 8 9 10 Press Browse and locate the file slabw2k inf The drivers were copied to the SiRFDemo directory during the SiRFDemo
49. cument including but not limited to claims or damages based on infringement of patents copyrights or other intellectual property rights SiRF makes no warranties either express or implied with respect to the information and specifications contained in this document Performance characteristics listed in this data sheet do not constitute a warranty or guarantee of product performance All terms and conditions of sale are governed by the SiRF Terms and Conditions of Sale a copy of which you may obtain from your authorized SiRF sales representative Getting Help If you have any problems with your product contact your SiRF representative or call or send an e mail to the SiRF Technology support group phone 1 408 467 0410 e mail support sirf com SiRFDemo User Guide June 2007 Contents yuk couvsvaeee epee AP Vil L OVCRVICW sss lt erewenteseGbeacasawee ieeetteeaded eae sass 1 1 Supported Products aaa 1 1 SiRFDemo MENuS 0 0 eee eee eee 1 2 2a PAN AA APA 2 1 Computer Requirements 4 cee eee ee ee eee 2 1 Installing SiRFDemo 1 eee 2 1 Installing USD Drivers pasamain BALA O KAKANAN EY K UAE cess 2 2 Windows XP Installation aa 2 3 Windows 2000 Installation a 2 3 Windows 98 Installation aa 2 4 Connecting a GPS Receiver 0 0 a 2 4 Quick Stai eeaeee o oo he be Sa OES Oe eee oP RS 2 5 3 Using the SiRFDemo Software ccc ccc eceeccecs 3 1 The S
50. d periodically so that it operates only a fraction of the time Power is applied only when a position fix is scheduled Push to Fix In Push to Fix mode the GPS receiver is generally off but turns on frequently enough to collect ephemeris data to maintain the GSPI real time clock calibration so that upon user request a position fix can be provided quickly after power up Note Low power mode is not supported by SiRFDRive This menu is disabled when SiRFDemo is set up for SiRFDRive TricklePower In this mode the power to the GRF21i LP chip is cycled regularly according to two user specified parameters Update Rate OnTime Maximum Off Time Maximum Search Time During TricklePower operation the GRF2i LP chip is powered on for OnTime in milliseconds then powered off for a specified number of milliseconds as determined by the update rate This cycle repeats indefinitely The GSP2e LP chip is not explicitly powered down but its primary operation is driven by the GPS clock generated by the GRF21 LP so it draws very little power while the GRF2i LP is powered down The real time clock RTC portion of the GSP2e LP continues operation at all times and is used to generate the interrupt that turns everything back on The microprocessor on which the SiRF code executes is not explicitly powered down After the OnPeriod has elapsed the processor continues operating long enough to complete its navigation tasks then puts itself in
51. d when a minimum number of satellites are not available to calculate a full 3D position Note Degraded mode is not supported in GSW3 2 5 and newer To set the navigation mode control 1 Select Mode Mask from the Navigation menu The Navigation Moding screen is displayed Navigation Moding Default X W Enable Track Smoothing Cancel Altitude hold mode te Automatic f Last computed altitude Always Fixed altitude m jo Disable altitude hold Degraded mode Use direction then clock hold f Use clock then direction hold Direction curb hold only Timeout s po Clock time hold only C Disable degraded mode Dead Reckoning fw Enable DR mode Timeout s E 2 Select the required navigation mode options Table 3 15 Navigation Mode Options Option Description Default Enable Track Enables smoothing of the calculated positions based on acceptable Off Smoothing variances from the last calculated position This assists in eliminating any sporadic position jumps possibly caused by multipath for example Altitude Hold Mode Automatic Switch automatically to a 2D solution and hold the altitude fixed On when only three satellites are available A 3D solution is calculated when four or more satellites are available 3 57 IH Oo Table 3 15 Navigation Mode Options continued Option Description Default Always Stay in 2D mode regardless of the number of satellites avai
52. d with additional applications for post processing data analysis Note Third party analysis tools are not provided in SiRF evaluation or system development kits 3 35 IH Oo A list of supported data types is available in Table 3 12 Table 3 12 Additional File Formats File Format Use KML Keyhole Markup Language a file format used to display geographic data in an Earth browser such as Google Earth M or Google Maps M To open a file and select messages to log 1 Click the Log File Settings button or select Open Log File from the Action menu 2 Check the box next to the additional file format you would like to log The Log File Settings window is displayed Log File Settings Filename sitfstar gps Hi Messages Available for Logging Cancel 001 Ref Nav undefined Meas N F Hii bia recommended Raw Trk S Aa Version Select All Clk Status E0 BPS Select None Thru put Error Command Ack Command Mak 013 Visible List 014 Almanac E phemers Haw DGPS Revi Params DGPS Status Mav Lib Meas Timer Record Log File only During a Specified Time Interval Start Time 11 43 34 AM 6219 2007 w End Time 12 43 34 Pk 6 19 2007 w Duration zec Additonal Logging IY KML sirfstar kmil Eal Note Only KML format data logging is available at this time 3 Enter the desired log file name and location in the provided field 4 Click OK to begin logging the selected mes
53. de Testing Timeout 5 18 default Health 0N Correction ON ooo oo A m A a S oe oo oS The following table provides a description of each of the displayed items Information Description Source GPS Corrections Internal DGPS Beacon Receiver SBAS Displays the source of the current DGPS corrections Displays the PRN pseudo range correction received and the age of the correction for each satellite Displays where the correction was received from The possible sources are external RTCM internal beacon and WAAS For example when the internal beacon see footnote is the DGPS source the following information is displayed Locked Status of tracking Coast Guard Beacon Frequency Frequency KHz of beacon tracked Bit Rate Bits per second bps for signal demodulation Signal Magnitude Variable Signal Strength Variable SNR Signal to Noise Ratio TBD Displays information about the current SBAS operation if used The information includes PRN The unique SBAS satellite identifier Mode Testing or Integrity monitored Timeout The time out of SBAS corrections Health Health status of the SBAS corrections Correction SBAS correction The Geodetic Nav View Screen The Geodetic Nav View screen provides data about the current navigation and position performance To view the Geodetic Nav View screen 1 Select Messages Geodetic Nav from the View menu SiRFDemo User Guide June 2007 U
54. e Royal Observatory which was located at Greenwich just outside London England Longitude runs from 0 at the prime meridian to 180 east or west halfway around the globe When not qualified with letters E or W it is assumed positive is east of Greenwich and negative is west of Greenwich The International Date Line follows the 180 meridian making a few jogs to avoid cutting through land areas Low Power Time Source Least Significant Bit or Bytes of a binary word Local Tangent Plane coordinate system The coordinates are supplied in a North East Down sense The North and East are in degrees or radians and Down is height below WGS 84 ellipsoid in meters Meters per second unit of velocity Meters per second per second unit of acceleration Meters per second per second per second unit of impulse or jerk An angle of elevation angle above the local horizontal which is the limit for using satellites in a navigation solution Because low elevation satellites tend to have more multipath problems GPS receivers set a mask angle and will not use satellites whose elevation is below that angle Typical mask angles are 5 10 and 15 Message Identifier In the case of SiRF binary protocol it is a number between 1 and 255 SiRF Demo User Guide June 2007 MIPS MHz MSB MSL MTBF MUL Multipath Error mV mW NED Navigation Message NF NMEA NVRAM Obscuration OEM Overdetermined Solution P Code Pa
55. elocity position and clock information Startup initialization information Navigation data Analog Digital Converter Odometer Diagnostic mode SiRFDRive data SBAS operation data Time information for the 1 PPS output Diagnostic mode SiRF extended ephemeris output message SiRFDrive dead reckoning SiRF Demo User Guide June 2007 Oo IH Table 3 11 Messages That Can Be Logged to a File continued Messages Description 225 Stats Channel Reports stats about startup time and encrypted messages 232 SEA Input SiRF extended ephemeris input message 255 Debug Various development information Adding Text to a Log File During logging of data it is possible to place a text entry into the file during logging Note The Put Text Into Log File option is only available while a log file is being collected To add a text entry into the current log file 1 Select Put Text Into Log File from the Action menu The Enter Text Message To Insert Into Log File screen is displayed Enter Text Message To Insert Into Logfile X Cancel 2 Enter the text to be placed into the text file 3 Click OK The log file is annotated with a line displayed the following format User Text hh mm ss lt entered text gt Logging Additional Data Using the SiRF Demo Software The user has the option of logging data in additional file formats while concurrently logging gps data These are common file formats that can be use
56. emo Software Oo IH The Log File Settings window is displayed Log File 5ettings Filename sitfstar gps Bi Messages Available for Logging Cancel 001 Ret Nay undefined Meas N al Ha ta recommended Raw Trk SAW Version Select All Clk Status E0 BPS Select None Thru put Error Command Ack Command Nak 013 Visible List 014 Almanac Ephemerls Raw DGPS Rev Params DGPS Status Nav Lib Meas Timer Record Log File only During a Specified Time Interval Start Time 11 09 27 AM za 6 19 2007 End Time 12 09 27 PM 6219 2007 w Duration sec 3600 Additional Logging M KML 2 Select each message you want to log to a file by clicking the required message Select all of the messages at once by clicking Select All Note Only records that are selected are logged to a file When logging all available messages use 38400 Baud or higher This ensures that no data is lost during logging 3 Check the Record Log File Only During a Specified Time Interval checkbox to designate a particular logging interval and enter the start time stop time and date 4 Check the Record Log File Only During a Specified Time Interval checkbox and enter in the Duration field a particular duration in seconds after which the logging session is closed 5 Click OK to begin logging the selected messages or Cancel to abort opening a file During logging logging status is displayed at the bottom of the SiRFDemo screen Loggi
57. eral subids are handled 255 sub id 1 and sub id 3 This window is designed specifically for GSW 3 2 development and for future extended ephemeris products Message 30 pertains to all software except SiRFXTrac Message 56 pertains only to GSW3 MID 48 SubID 1 DR Navigation Status MID 48 SubID 2 DR Navigation State MID 48 SubID 3 Navigation Subsystem MID 48 SubID 8 DR Data Block SiRFDRive 1 x Gyro and Odo Sensor Data MID 172 SubID 9 Wheel Speed and Odo 2 0 Sensor Data SiRFDRive 2 x MID 172 SubID 14 Gyro and Accelerometer Sensor Data SiRFDiRect MID 172 SubID 14 Gyro and Accelerometer Sensor Data SiRFDiRect SiRF Demo User Guide June 2007 File Formats B This appendix describes the format of files that are either used by the SiRFDemo software or are created by the SiRFsig software It includes information on the following e Modifying the Sample sirf pos File e Description of SiRFsig File Formats Modifying the Sample sirf pos File The sirf pos file can be used by the Receiver Initialization dialog to load predefined coordinates To modify the sirf pos file 1 Open the sample sirf pos file using a text editor The sample X Y Z positions are displayed s2080 110 4304272 5001050 O 2 Use the configuration values displayed on the Measured Navigation Message View screen as your new X Y and Z coordinates after communication is established with the GPS receiver i Measured N
58. erial port is not desired do not check the Create Virtual Serial Port option on the Setup menu The virtual serial port will be created and opened when the primary serial connection is established and it will be closed and removed when the primary serial connection is closed A separate application will be able to open the virtual serial port to receive the piped data output Note At this time only NMEA data can be output through the virtual serial port If operating in SiRF Binary serial data input will be converted to NMEA before being piped out the virtual serial port To use the auxiliary data source 1 Select Data Source from the Setup menu The Data Source Setup screen is displayed Data Source Setup Serial Port COM1 Baud Rate 57600 Cancel C Ref o o C Random Virtual Serial Port Data Piping I Create Virtual Serial Port Port COM7 v Protocol Aux Data Source Use Sux Data Source Pott Baud Rate 2 Check the Create Virtual Serial Port checkbox 3 From the Virtual Port Data Piping Port pulldown menu select the virtual port through which serial data will be output 4 Choose the desired output Protocol from the pulldown menu Note Only NMEA data piping is available at this time 5 Click OK to accept selected settings 3 6 Note If Virtual Serial Port Drivers have not yet been installed you will be prompted to install at this time Follow onscreen instruction
59. es and finishing at the zenith 90 degrees Bin Bin Avg C No of Data Max C No Min C No 34 04 37 00 29 00 38 58 1638 43 00 33 00 1 00 99 00 37 00 28 00 46 00 35 00 1 00 99 00 This is the start and end time of the data session in GPS seconds into the week Start End 259510 24 263143 18 This is the average position of the board receiver in ECEF XYZ coordinates Px Py Pz 2686753 9 4304226 9 3851670 2 This is the average velocity of the board receiver in ECEF XYZ coordinates Vx Vy VI 2686753 9 4304226 9 3851670 2 This is the board receiver software version Version 200R00234 This is the data protocol of the board receiver 201 protocol 1 20 equals SiRF Binary data 21 equals NMEA data This is the Power settings of the board receiver Power Mode 10 1000 0 1 0 mode Ontime ms Update Rate ms 1 10 equals Full Power 11 equals Trickle Power 12 equals Push to fix 2 User selected On Time in ms 3 User selected Update Rate in ms This is the Elevation Mask in degrees Elevation Mask 7 5 This is the DGPS mode of operation DGPSmode 10 10 Auto 11 Exclusive 12 Never Use B 3 B 4 pos File vel File AH File x sys File This is the Number of False Acquisitions Detected False Acquisitions 0 x pos is the time tagged position file in ECEF XYZ parsed from record 002 measured navigation
60. esumes operation using SiRF binary protocol and 38400 Baud Since the receiver should also be operating with the same settings at this time communication resumes Using the SiRF Demo Software 3 43 Hi Oo Switching to Userl Protocol When a user protocol is defined and implemented in the version of software running the Switch to Userl menu item can be used to enable the user defined protocol When Switch to Userl is selected the target platform changes to the user defined protocol but SiRFDemo continues to operate in SiRF Binary Note When the target platform is operating in the user defined protocol there is no direct method through SiRFDemo to switch the target platform back to SiRF Binary An application based on the user protocol must be used or the Send Serial Message ability may be utilized To change the operating protocol to a user defined protocol 1 Select Switch to User1 Protocol from the Action menu Setting the Main Serial Port Use the Set Main Serial Port function to change the Baud rate of the serial port connected to the GPS receiver and the serial port of the computer To change the Baud rate of the port used by the GPS receiver and the computer 1 Select Set Main Serial Port from the Action menu The Set Serial Port Parameters screen is displayed Set Serial Port Parameters X Baud Rate 38400 7 CU p E Data Bits 5 ance Parity NONE Stop Bits i 2 Select the Baud rate fr
61. etis Files eph Cancel A 2 Select the file you want to use 3 Click Open Note The ephemeris file must be in the same format as polled from a SiRF GPS receiver To download an ephemeris file from a GPS receiver see Downloading an Ephemeris File on page 3 68 Opening an Extended Ephemeris File An extended ephemeris is used by a GPS receiver to quickly calculate a position fix while the GPS receiver is still downloading a broadcast ephemeris When an extended ephemeris file is not available or has expired it must be downloaded from the SiRFInstantFix server See the SiRFGetEE User Guide for instructions about getting an extended ephemeris To open an extended ephemeris file 1 Select Extended Ephemeris from the Action menu The Specify EE File screen is displayed Specify EE File Look in B My Documents B Febz ee E FEB ee E march ee File name Files of type EE Files 26 w Cancel Open as read only 2 Select the file you want to use 3 Click Open 3 48 SiRF Demo User Guide June 2007 Oo IH Switching Operating Mode Using the SiRFDemo Software It is possible to place a GPS receiver into a test operating mode This mode allows a single selected satellite to be tracked by all 12 channels of the GPS receiver To place a GPS receiver into test mode 1 Select Switch Operating Mode from the Action menu The Operating Mode screen is displayed
62. etup MCG awa AMA ooo bi eeecus cede we aes sen bee 3 1 Selecting the Target Software eee eee ee 3 1 GPS Time PO DING Xa hak deg Rhee ec DADA NEEE 3 2 Defining the Data Source a 3 3 Aux Serial Port Message Forwarding 3 4 Virtual Serial Port Data Piping 0 00 000 ee 3 5 Changing Preferences 0 a 3 6 ill Displaying Information About the SiRFDemo Software 3 7 Exiting the SIRFDemo Software 4 aa 3 7 Te View Menu chka ec eee ane ong NAGAGANAP eee ee 3 7 The 12 Channel Signal Level View Screen 3 8 The Radar View Screen 0 ccc cece eee eens 3 11 The Map VIEW Screen 4 044 464 deueSeurcaebaucaaeneeeas 3 12 The Navigation Message View Screen 3 14 The Response View Screen 0 0 00 cece eee eee ee 3 15 The Output View Screen 0 0 0 ee eee 3 16 The Error Message View Screen 0 000 eee eee 3 16 The Debug Data View Screen ee eee eee 3 17 The DGPS View Screen lt 2044 4 44 400ebwe es een BANA nake 3 17 The Geodetic Nav View Screen aaa 3 18 The PPS Timing View Screen 444 442 kaawa waaa LANG 3 20 Aux Output View Screen 0 0 0 cece eee 3 21 SIRFDrive VIEW Screen 3 3 na a a GAB cs geseaceoansdotwodes 3 22 DR NAV SUBSYSTEM DATA 2 0020 coco 3 25 SiRFDRive Sensor View Screen o 3 26 SiRFDiRect Graph View Screen a 3 28 Ephemeris Informat
63. everse Reverse indicator 3 27 IH Oo Table 3 10 SiRFDiRect Sensor Package Field Items continued Item Description Time Sensor time in seconds does not correspond with GPS time Validity Binary validity code Gyro Rate of rotation about yaw axis in degrees per second Gyro2 Note Pitch gyro not present in all SiRFDiRect evaluation receivers Rate of rotation about pitch axis in degrees per second Down Acc Downwards acceleration in meters per second squared Lat Acc Lateral acceleration in meters per second squared Long Acc Longitudinal acceleration in meters per second squared SiRF DiRect Graph View Screen The SiRFDiRect Graph View screen graphically displays the acceleration and rotation data output by the onboard gyro and accelerometers updated at 1 Hz The 3D frame will color green as acceleration occurs in that direction Likewise the circles will fill in green as the receiver is rotated Graph will reflect changes in receiver orientation in real time To view the SiRFDiRect Graph View screen 1 Select Messages SiRFDiRect Graph from the View menu YSiRFDiRect Graph View 3 28 SiRF Demo User Guide June 2007 Ephemeris Information Using the SiRFDemo Software To view the Ephemeris Info View screen 1 Select Messages Ephemeris Info from the View menu The Ephemeris Info View screen is displayed TVEphemeris Info View _ fox 3iFF Binary Msg 56 SubID 55 ACK Disable Broadcast Ephemeris Dis
64. f the speed sensor Calibration status specifically for gyro bias System has performed the special bias calibration that is done when the vehicle is stationary Calibration status specifically for gyro scale factor Status of whether the gyro bias or scale factor 1s updated during the cycle Calibration status specifically for the speed sensor scale factor Status of whether the speed sensor calibration updated during the cycle Calibration status of the differential wheel speed heading rate scale factor Update status of the differential wheel speed heading rate scale factor Calibration status of the differential wheel speed scale factor Update status of the differential wheel speed scale factor Note When the status is invalid one or more of the bits appears in upper case Using the SiRF Demo Software 3 23 3 24 DR NAV STATE The following table provides a description of each of the displayed items for the DR NAV STATE field Item paa DR Spd DR Spd Error DR Spd SF DR Spd SF Error DR Hdg Rte DR Hdg Rte Error DR Hdg Rte SF DR Hdg Rte SF Error DR Hdg DR Direction Total DR Hdg Error Total DR Pos Error Sensor Package Gyro Bias Gyro Bias Error Odo Speed Odo Spd SF LF Wheel Spd SF LF Wheel Spd SF Error RF Wheel Spd SF RF Wheel Spd SF Error LR Wheel Spd SF LR Wheel Spd SF Error RR Wheel Spd SF RR Wheel Spd SF Error F Axle Spd Delta F Axle Avg Spd F Axle Avg Spd Error
65. from the View menu The Aux Output view screen is displayed Using the SiRFDemo Software 3 21 3 22 SiRF Drive View Screen The SiRFDRive view is only available when SiRFDRive or SiRFDiREct are selected as the target software The SiRFDRive View screen provides the DR navigation status and DR sensor data The screen is divided into the following fields DR Navigation Status DR Navigation State e Navigation Subsystem Data To view the SiRFDRive View screen 1 Select Messages SiRFDRive from the View menu The SiRFDRive View screen is displayed TISiRFDRive Status View Sic DR NAY STATUS DR NAY STATE DR Nav DR Spd DR Data DR Spd SF DR Cal DR Hdg Rte DR Pos DR Hdg Rte SF DR Hdg DR Hdg DR Nav across Reset Total DR Hdg Error DR Nav St Int Ran Total DR Pos Error DR Nav State Upd Sensor Package Gps Pos Upd aha ine ae Error 000 00 Gps Hdg Upd o speed Ba Tig nag DR Odo Spd SF Error 000 00 Gps Vel for DR LF Wheel Spd SF Error 000 00 Gyro Subsys Op RF Wheel Spd SF Error 000 00 Odo Speed Subsys Op LR Wheel Spd SF Error 000 00 Gyro Bias Cal RR Wheel Spd SF Error 000 00 0 Spd Gyro Bias Cal Upd F Axle Spd Delta Gyro SF Cal F Axle Avg Spd Error 000 00 Gyro Bias amp SF Cal Upd F Axle Hda Rte Error 000 00 Odo Speed SF Cal F Axle Spd Delta HE Mina R Avle Avg Spd Error 000 00 DWS Hdg Rate SF Cal R Axle Hdg Rte Error 000 00 D w 5 Hdg Rate SF Upd DWS Speed SF Cal NAY SUBSYSTEM DA
66. g changes SiRFDemo User Guide June 2007 Oo IH Displaying Information About the SiRFDemo Software 1 Select About SiRFDemo from the Setup menu to display SiRFDemo software information About SiRFDemo SiRFD emo 3 83 mo Copyright 2005 SIRF Technology Inc Exiting the SURF Demo Software The View Menu Using the SiRF Demo Software 1 Select Exit from the Setup dropdown menu This closes SiRFDemo software This section describes the SiRFDemo functions on the View menu NSiRFDemo fate Action Navigation Poll Window f w m Radar Lai ial Ka Tracking Navigation Response Output w Error w Debug DGPS Geodetic Nay PPS Timing AUX Output Ephemeris Info m Signal Level The 12 Channel Signal Level View Screen on page 3 8 The Radar View Screen on page 3 11 The Map View Screen on page 3 12 The Navigation Message View Screen on page 3 14 e The Response View Screen on page 3 15 e The Output View Screen on page 3 16 e The Error Message View Screen on page 3 16 e The Debug Data View Screen on page 3 17 3 7 3 8 e The DGPS View Screen on page 3 17 The Geodetic Nav View Screen on page 3 18 The PPS Timing View Screen on page 3 20 e Aux Output View Screen on page 3 21 e SiRFDrive View Screen on page 3 22 e SiRFDRive Sensor View Screen on page 3 26 e SiRFD
67. gation Parameters Parameter Description AltMode Selected altitude hold mode AltSource Altitude type used when a 2D solution is being calculated Altitude Altitude used when fixed manually DegradeMode Type of degraded mode selected DegradedTimeout Timeout value applied to degraded mode operation DR Timeout Timeout value applied to dead reckoning navigation TrkSmoothMode Enable or disable state of track smoothing StaticNav Enable or disable state of the static navigation mode 3SV LSQ Indicates the state of a start up mode that allowS start up when only three satellites are available DOPMaskMode Selected DOP mask control ElevMask Currently used elevation mask PwrMask Currently used power mask DGPSSrc Selected DGPS source DGPSMode Selected DGPS mode SiRF Demo User Guide June 2007 Uo Hi Table 3 16 Navigation Parameters continued Parameter Description DGPSTimeout Timeout value applied to DGPS corrections Power Mode indicates the current power mode of the GPS receiver which is either TricklePower or continuous power User Task User status enabled or disabled default MaxAcqTime Maximum Acquisition Time MaxOffTime Maximum Off Time Downloading an Almanac File Using the SiRFDemo Software You can download an almanac file from a SiRF GPS receiver and load it back into the receiver at a later date or to another GPS receiver This is to assist with initial satellite tracking This file
68. he appropriate SiRF Binary start sequence payload length message checksum and end sequence is calculated and added to the payload NMEA The appropriate NMEA format start sequence message Off 8 S lt data gt ck r n checksum and end sequence is calculated and added to the payload None HEX Converts Hex to binary with no additional header Off 8 None ASCII Sends ASCII data Off 8 4 Click Send to send the defined message to the target platform This section describes the SiRFDemo software functions under the Navigation menu SiRF Demo Setup View Action QREMIeEiie Poll Window el na Ha lo Mode Mask Bi a i DOP Mask Elevation Mask Power Mask Static Navigation DGPS Mode DGPS Source SBAS Control Setting Mode Mask Control on page 3 57 Setting the DOP Mask Control on page 3 59 Selecting an Elevation Mask on page 3 59 e Selecting a Power Mask on page 3 60 e Enabling Disabling the Static Navigation on page 3 61 SiRFDemo User Guide June 2007 Uo IH e Setting the DGPS Mode on page 3 61 Selecting the DGPS Source on page 3 62 Setting the SBAS Operating Mode on page 3 63 Setting Mode Mask Control Using the SiRFDemo Software Navigation mode control is used to configure the specifics of how a GPS receiver navigates or calculates a position In particular selecting how a position should be derive
69. he number of Off 8 satellites available Use HDOP only Only the HDOP mask is used regardless of the number of Off 8 satellites available Use GDOP only Only the GDOP mask is used regardless of the number of Off 8 satellites available Do not use No DOP based mask is applied Any available position is On output regardless of any of the DOP values 3 Enter a DOP mask value for the corresponding selected DOP mask For each of the DOP masks the default value is 10 This value is a maximum value and the mask applies when the current set mask is exceeded 4 Click Send to accept or Cancel to exit Selecting an Elevation Mask GPS satellites that are low on the horizon are subject to noise due to the amount of atmosphere that the signal must travel through Better position accuracy is often achieved when lower elevation satellites are not used in the position solution The elevation mask is used to exclude the use of satellites in the position solution that are below a defined elevation mask Using the SiRF Demo Software 3 59 IH Oo To select an elevation mask 1 Select Elevation Mask from the Navigation menu The Elevation Mask screen is displayed Elevation Mask Default x Set minimum satellite elevation angle to be required for Navigation deg 7 5 2 Enter the minimum elevation angle for satellites to be used in any position solution 3 Click Send to accept or Cancel to exit Selecting a
70. hen the selected software target is 2 3 See The View Menu on page 3 7 for detailed information about the View menu The Action menu provides access to most of the SiRFDemo functionality such as configuration of the connected GPS receiver data logging for later analysis the extended ephemeris features See The Action Menu on page 3 31 for detailed information about the Action menu The Navigation menu lets you configure items that effect how a position solution is acquired or the type of position needed From the Navigation menu you can set various operating masks the DGPS mode and the DGPS source See The Navigation Menu on page 3 56 for detailed information about the Navigation menu SiRF Demo User Guide June 2007 Overview Pana IH Table 1 1 SiRFDemo Menus Continued Menu Description Poll The Poll menu is used to obtain information about the attached GPS receiver such as software version navigation parameters and clock status You can also use the Poll menu to obtain the latest ephemeris almanac and extended ephemeris See The Poll Menu on page 3 64 for detailed information about the Poll menu Window The commands on the Window menu commands control the appearance of the information displayed SiRFDRive The SiRFDRive menu is used to provide control of a SiRFDRive or SiRFDiRect enabled product This menu is only available when SiRFDRive SiRFDiRect or SiRFDRive and SiRFNav are selected as
71. iRect Graph View Screen on page 3 28 e Ephemeris Information on page 3 29 The 12 Channel Signal Level View Screen The 12 Channel Signal Level View screen is a combined graphical and text display of satellite tracking Information shown by the Signal Level view includes satellite number status azimuth elevation C No and last five seconds of measured signal strength To display the 12 Channel Signal Level view screen 1 Click the Signal Level View button or select Signal Level from the View menu Note The Preferences screen allows you to modify the way information is displayed Double click the 12 Channel Signal Level View screen to display the Preferences screen Table 3 1 12 Channel Signal Level View Information Information Displayed Description Satellite Number SV The GPS satellite PRN number Status St The status of each satellite tracked see Table 3 2 Tracking Status Definitions on page 3 9 for more information Azimuth Az Satellite azimuth in degrees SiRF Demo User Guide June 2007 Uo Hi Table 3 1 12 Channel Signal Level View Information Information Displayed Description Elevation El Satellite elevation in degrees with the horizon being zero degrees in elevation and directly over head being ninety degrees C No Signal level in dB Hz Signal Level 5 sec Five second history of the measured signal strength Table 3 2 represents each of the pos
72. iews please see The View Menu on page 3 7 When no information is displayed on any of the screens ensure that The receiver is switched on and has a clear view of the sky The serial cable is correctly connected The correct serial port and baud rate are selected in the Data Source Setup dialog under the Setup menu Finally select Synchronize Protocol amp Baud Rate from the Action menu SiRF Demo User Guide June 2007 The Setup Menu Using the SiRF Demo Software 3 Before running the software connect the SiRF GPS receiver to the PC ensure it is powered on and that the antenna has a clear view of the sky For full installation instructions see Chapter 2 Getting Started To start the SiRFDemo software either double click the sirfdemo exe file or the shortcut on your desktop This section describes the SiRFDemo functions on the Setup menu SiRFDemo i View Action Navigation Target SAN Data SOUPCE PE Data Source GPS Time gt PC Time Preferences About SIRFDeme Exit Selecting the Target Software on page 3 1 Defining the Data Source on page 3 3 GPS Time PC Time on page 3 2 Changing Preferences on page 3 6 Displaying Information About the SiRFDemo Software on page 3 7 Exiting the SiRFDemo Software on page 3 7 Selecting the Target Software SiRF Demo User Guide June 2007 The SiRFDemo software support
73. installation By default the directory is C Program Files SiRF SiRFDemo usbDrivers Press Finish to complete the installation of the CP2101 USB to UART Bridge Controller Windows 98 Installation To install the required USB drivers on Windows 98 l Connect the USB enabled SIRF GPS receiver to your PC Windows opens a Found New Hardware Wizard window Press Next to continue Select Search for the best driver for your device Recommended and press Next Select Specify a location Press Browse to locate the directory where the drivers are located and press Next The drivers were copied to the SiRFDemo directory during the SiRFDemo installation By default the directory is C Program Files SiRF SiRFDemo usbDrivers Press Finish to complete the installation of the CP2101 USB Composite Device Windows now opens a second Found New Hardware Wizard window Press Next to continue and follow steps 2 through to 5 Press Finish to complete the installation of the CP2101 USB to UART Bridge Controller Connecting a GPS Receiver To connect a SiRF GPS receiver ready for operation with SiRFDemo 1 Connect the GPS antenna to the antenna GPS input on the GPS receiver and place the antenna in a location where it has a clear view of the sky Connect one end of a serial cable to the appropriate communications port on your computer Connect other end
74. ion 0 0000 e eee eee eee 3 29 The AcChion Menu comma oebngad ddstuwderotevescesiids 3 31 Opening a Data Source a 3 32 Opening a Log PING amahan wa 640 q404 eee sees ee GANG t 3 32 Adding Text to a Log File 2 0 eee 3 35 Logging Additional Data a 3 35 Pausing the Display 20 0 ccc eee ee eee 3 37 Initializing the Data Source a 3 37 Switching to the NMEA Protocol 00005 3 42 Switching to the SiRF Binary Protocol 3 43 Synchronizing Protocol and Baud Rate 3 43 SiRF Demo User Guide June 2007 Contents Switching to Userl Protocol aaa 3 44 Setting the Main Serial Port 0 0 0 0 cee eee 3 44 Setting the DGPS Serial Port Parameters 3 45 Setting the UART Configuration 005 3 45 Uploading an Almanac to a GPS Receiver 3 47 Uploading an Ephemeris to a GPS Receiver 3 47 Opening an Extended Ephemeris File 3 48 Switching Operating Mode a 3 49 Disabling a Broadcast Ephemeris 0005 3 50 Setting Low Power Parameters a 3 51 Setting Advanced Power Management Options for SiRFXTrac 3 54 Setting the Message Rate 4 3 aa NAAGAW LA GA 3 54 Transmitting a User Defined Serial Message 3 55 The Navigation Menu 22642444544446h0s0deeeeeaucadedas 3 56 Setting Mode Mas
75. ion Menu Using the SiRFDemo Software Uo Hi This section describes the SiRFDemo functions on the Action menu Navigation Poll Window ol Open Data Source Open Log File Pause Display Initialize Data Source Switch to NMEA Protocol Synchronize Protocol amp Baud Rate Switch to User1 Protocol Set Main Serial Port Set DGPS Serial Port Set WART Configuration Set Almanac Set Ephemeris Set Extended Ephemeris Switth Operating Mode Disable Broadcast Ephemer is Set Low Power Trickle Power Set Message Rate Transmit Serial Message Opening a Data Source on page 3 32 Opening a Log File on page 3 32 e Adding Text to a Log File on page 3 35 e Pausing the Display on page 3 37 e Initializing the Data Source on page 3 37 ih Open Data Source not connected Open Data Source connected LJ Open Log File Ji Pause Display 25 Ole S PE Initialize Data Source Switching to the NMEA Protocol on page 3 42 Switching to the SiRF Binary Protocol on page 3 43 e Synchronizing Protocol and Baud Rate on page 3 43 Switching to Userl Protocol on page 3 44 Setting the Main Serial Port on page 3 44 Setting the DGPS Serial Port Parameters on page 3 45 Setting the UART Configuration on page 3 45 e Uploading an Almanac to a GPS Receiver on page 3 47 e Up
76. ion for a satellite SiRF Demo User Guide June 2007 TDOP 3 D Coverage 3 D Navigation TTFF 2 D Coverage 2 D Navigation UART UDRE UERE Update Rate UTC VCO VDOP VSWR Warm Start WGS 84 Acronyms and Abbreviations Glossary C Time Dilution of Precision A measure of how much the geometry of the satellites affects the time estimate computed from the satellite range measurements The number of hours per day with four or more satellites visible Four visible satellites are required to determine a three dimensional position In the GPS constellation with full operational configuration consisting of 21 primary satellites and at least 3 in orbit spares 3 D coverage is available at all times over the surface of the earth Navigation Mode in which altitude horizontal position and the local time are determined from satellite range measurements Time To First Fix The actual time required by a GPS receiver to achieve a position solution after power is applied or a reset is performed This specification varies with the operating state of the receiver the length of time since the last position fix the location of the last fix and the specific receiver design See also Hot Start Warm Start and Cold Start The number of hours per day with only three satellites visible Three visible satellites can be used to determine location if the GPS receiver is designed to accept an external altitude input Altitude
77. itude above mean sea level in meters Map Datum The currently used map datum HDOP Horizontal Dilution of Precision SOG Speed Over Ground in meters second 3 19 3 20 Table 3 6 Geodetic Nav View Screen Displayed Items continued Information Description Heading Direction of movement COG Course Over Ground in degrees Hdg Error The current heading error in degrees Mag Var The currently used magnetic variation in degrees Clmb Rte The change in altitude over time in meters second Hdg Rte The change in heading over time in degrees second EHPE Estimated Horizontal Position Error in meters EVPE Estimated Vertical Position Error in meters ETE Estimated Time Error in meters EHVE Estimated Horizontal Velocity Error in meters second Clk Bias Error Clk Drft Error Traveled Error DR Direction Map Matching Feedback Input Map Matching Feedback Revd Map Matching Feedback Used in Solution The current clock bias and error in meters The current clock drift and error in meters second error in meters The distance travelled since reset and the associated error in meters When using the SiRFDrive software tool the dead reckoning sensor detects forward or reverse speed N A indicates product does not support map matching Flags indicate enabled disabled or true false map matching N A indicates product does not support map matching Flags indicate enabled disabled or true false map matching N
78. k Control 2 3 57 Setting the DOP Mask Control 0 0 0 0 00s 3 59 Selecting an Elevation Mask 0 0 0 0 c eee eee 3 59 Selecting a Power Mask 1 0 0 cece eee 3 60 Enabling Disabling the Static Navigation 3 61 Setting the DGPS Mode 0 00 ee eee 3 61 Selecting the DGPS Source 0 0 0 3 62 Setting the SBAS Operating Mode 05 3 63 The VOU Mei oeitcecnsswycehddgesaneeeaa goers e eens oo 3 64 Viewing the Software Version 0 ce eee nee 3 65 Polling the Clock Status 20 0 0 0 ccc nes 3 65 Polling the Navigation Parameters 000000 3 66 Downloading an Almanac File 0 0005 3 67 Downloading an Ephemeris File 0000 3 68 Polling the Ephemeris State 0 0 0 0 00 eee 3 68 Polling the Extended Ephemeris 005 3 69 v VI The SiRFDRive Menu 24 3 69 Setting Navigation Mode Control 005 3 70 Calibrating the GYfO0 n2 a na RB md DANG eh4 eed DA wok ee 3 70 Setting DR Sensor Parameters aa 3 71 Polling Gyro Factory Calibration 3 72 Polling DR Sensor s Parameters 0 2 00 0 eee 3 72 SIRFDemo Real Time View Windows eeeee0 A 1 B Pile Formals na 0A D NANG NGA NAN E ALPA DNA B 1 Modifying the Sample sirf pos File 00005 B 1 Description of SiRFsig File Forma
79. lable The Off altitude always remains fixed Disable Only calculate 3D solutions When it is not possible to calculate a 3D Off Altitude Hold solution due to insufficient satellites no navigation is provided Last When the GPS receiver is operating in 2D mode the altitude is held Off Computed to the last known altitude calculated by the GPS receiver Altitude Fixed When the GPS receiver is operating in 2D mode the altitude is held Off Altitude to the value entered in the Fixed Altitude field Degraded Modes Use Direction When the number of available satellites is reduced to two the GPS Off then Clock receiver holds the elevation fixed and uses the last direction and Hold doppler values change in distance to continue positioning When the available satellites is then reduced to one the clock bias is then extrapolated Use Clock This mode is similar to the above Direction then Clock Hold mode On then Direction However the clock bias is extrapolated first and then the direction Hold and doppler measurements are used Direction This mode restricts positioning to using direction hold only and does Off Curb Hold not use the extrapolating the clock bias method Two satellites must Only be available Clock Time Positioning is restricted to using the clock bias extrapolation method Off Hold Only only and does not hold the direction Two satellites must be available Disable When less than three satellites are available no p
80. loading an Ephemeris to a GPS Receiver on page 3 47 Opening an Extended Ephemeris File on page 3 48 3 3 3 32 Switching Operating Mode on page 3 49 e Disabling a Broadcast Ephemeris on page 3 50 Setting Low Power Parameters on page 3 51 Setting Advanced Power Management Options for SiRFXTrac on page 3 54 Setting the Message Rate on page 3 54 e Transmitting a User Defined Serial Message on page 3 55 Note All values that appear in the dialog boxes under this menu are default values only To determine the current settings of all navigation parameters refer to Section Polling the Navigation Parameters on page 66 Opening a Data Source Before any data can be received from or sent to a GPS receiver a communications channel must be established or a data source must be opened To open a data source it 1 Click the Connect Disconnect button or select Open Data Source from the Action menu 2 Click the Connect Disconnect button again or select Open Data Source from the Action menu to disconnect communication to the GPS receiver Opening a Log File The log file function provides the ability to log selected information from a connected GPS receiver and store it to a file To open a file and select messages to log 1 Click the Log File Settings button or select Open Log File from the Action menu SiRF Demo User Guide June 2007 Using the SiRFD
81. lock status see Polling the Clock Status on page 3 65 navigation parameters see Polling the Navigation Parameters on page 3 66 ephemeris state see Polling the Ephemeris State on page 3 68 and gyro calibration verification see Polling Gyro Factory Calibration on page 3 72 To display the Response View screen 1 Select Messages Response from the View menu The Response View screen is displayed Response View Week 1365 TOW 34062599 EstGPS Time 340625999 me SY Cnt11 A Clock Dritt35602 Hz Clock Bias 26581 364 ns lt lt OW Version GSwWa 20 31 00 12 C33P1 00 Acknowledged MIB PallS wVersion Using the SiRFDemo Software 3 15 IH Oo 3 16 The Output View Screen The Output View screen is used to display the SiRF Binary message IDs that are currently being output by the attached GPS receiver To display the Output View screen 1 Select Messages Output from the View menu The Receiver Output View screen is displayed Ral Receiver Output iew 009 0 09 Throughput 004 0x04 Measured Tracking Data O02 x02 Measured Navigation Data 027 0216 DGPS Status 050 0x32 5BAS Parameters O52 034 MD PP5 Time O47 Ox29 Geodetic Navigation Data 004 0x04 Measured Tracking Data O02 Ox07 Measured Navigation Data 009 0 09 Throughput 027 Ox16 DGPS Status 050 0x32 5545 Parameters O52 034 MID PP5 Time The Error Message View Screen The Err
82. ly dispersed Monitor Stations used to manage the GPS satellites determine their precise orbital parameters and synchronize their clocks Decibel a unit of comparative measurement equal to 10log measurement reference Decibel Isometric Circular measure of power relative to an isometric antenna with circular polarization Decibels relative to 1 milliWatt Decibels relative to 1 Watt Direct Current Differential GPS A technique to improve GPS accuracy that uses pseudorange errors recorded at known locations to improve the measurements made by other GPS receivers A signal processing strategy that uses a measured Doppler shift to help a receiver smoothly track a GPS signal to allow a more precise velocity and position measurement The U S Government Department of Defense Dilution of Precision see GDOP HDOP PDOP TDOP and VDOP Dynamic Random Access Memory a form of RAM that maintains its contents as long as power is applied and periodic refresh reads are made If either power is lost of the refresh signal is not maintained the contents of the memory will become corrupted Digital Signal Processor Data Terminal Ready A hardware signal that is part of a serial data bus Earth Centered Earth Fixed A Cartesian coordinate system with its origin located at the mass center of the Earth and whose axes rotate with the Earth The coordinate system used by GPS to describe 3 D location For the WGS 84 reference ellipsoid ECEF coordin
83. m the bottom right corner of right corner of the the Initialization screen Initialization screen Select a Reset option by clicking the associated radio button The following table describes the additional reset options available when SiRFXTrac 3 0 amp 3 1 or 3 2 are selected from the Setup SW menu Reset Mode GPS Only Reset System Reset Disable Broadcast Ephemeris Description Only resets the GPS code without disturbing user defined data Forces the code to branch to the start of the Reset Vector 0x0 This causes GPS and user defined data to be reset to their default values This causes the receiver to not use broadcast ephemeris and to only utilize the ephemeris sent to the receiver This feature is used for testing the extended ephemeris Using the SiRF Demo Software 3 41 3 42 Switching to the NMEA Protocol SiRF GPS products support a subset of the NMEA protocol Rather than operating in the SiRF binary protocol you can change the protocol to NMEA for the port that is currently connected Note When operating in NMEA mode many of the SiRFDemo display windows and functions are not supported To change the protocol to NMEA for the port currently connected to your computer 1 select Switch to NMEA Protocol from the Action menu The Select NMEA Messages screen is displayed NMEA Setup MSS User 8 User 3 User 10 a jo l 0 D D o z Update rate 17n sec D to 255 Cancel
84. m rate of one per 255 seconds 4 Select the Baud rate from the Baud Rate dropdown menu 5 Click Send to save or Cancel to exit Note When NMEA is selected as the operating protocol the output messages can be viewed in the Development Data screen It can also be logged by using the same technique as a SiRF binary file Select 255 Development in the Log File Settings screen and check Enable Development Data in the Messages field of the Receiver Initialization screen Switching to the SiRF Binary Protocol When operating in SiRF binary protocol this menu item is unavailable It can be used however when operating in NMEA protocol to change the protocol to SiRF binary To change the operating protocol from NMEA to SiRF binary 1 select Switch to SiRF Protocol from the Action menu to return to the SiRF binary protocol Synchronizing Protocol and Baud Rate All GPS receiver settings including selected protocol and serial port settings are held in battery backed SRAM When the attached GPS receiver is power cycled these settings remain When the GPS receiver is left in an unknown state it is difficult to regain communication The synchronize protocol and Baud rate function attempts to change the serial port settings of the GPS receiver to a known state of SiRF binary and 38400 Baud This is done by issuing commands to the receiver using all possible Baud rates and NMEA and SiRF binary protocols After this is complete SiRFDemo r
85. menu The SiRFDRive DR Sensor s Parameters screen is displayed SIRFDRive DR Sensors Parameters X Baseline speed scale factor j E Baseline gyro bias Cancel Baseline gyro scale factor T Use default values 2 Enter the new parameters or check the Use default values checkbox 3 Click Send to accept the setting Using the SiRFDemo Software 3 71 Hi Oo Polling Gyro Factory Calibration This command provides status information during the Gyro Factory Calibration process Refer to Calibrating the Gyro on page 3 70 for usage Note This function is not available in SiRFDiRect Polling DR Sensor s Parameters This command reads the current DR sensor values Speed Scale Factor meters wheel tick Gyro Bias zero rate volt Gyro Scale Factor mV deg sec Note This function is not available in SiRFDiRect To read the current DR sensor parameter values 1 Select SiIRFDRive DR Sensor s Parameters from the Navigation menu The Response View screen is displayed GI SW Version 231 000 00050RC1BETA1 O Acknowledged MID OrOutS ID_PolldrSensParam Speed SF 4 00 m ticks Gyro Blas 1 25 m Gyro SF 11 10 nv deg 3 72 SiRF Demo User Guide June 2007 SiRFDemo Real Time View Windows A SiRFDemo provides view windows for real time monitoring of SiRF GPS receivers Each view windows displays information based on one or more SiRF Binary receiver output message s a
86. meter 1 km 1000 meters The 1575 42MHz GPS carrier frequency that contains the C A code P code and navigation messages used by commercial GPS receivers A secondary GPS carrier containing only P code used primarily to calculate signal delays caused by the atmosphere The L2 frequency is 1227 60MHz Halfway between the poles lies the equator Latitude is the angular measurement of a place expressed in degrees north or south of the equator Latitude runs from 0 at the equator to 90 N or 90 S at the poles When not qualified with letters N or S it is assumed positive is north of the equator and negative is south of the equator Lines of latitude run in an east west direction They are called parallels Latitude Longitude Altitude Geographical coordinate system used for locating places on the surface of the Earth Latitude and longitude are angular measurements expressed as degrees of a circle measured from the center of the Earth The Earth spins on its axis which intersects the surface at the north and south poles The poles are the natural starting place for the graticule a spherical grid of latitude and longitude lines See also Altitude Low Noise Amplifier Lines of longitude called meridians run in a north south direction from pole to pole Longitude is the angular measurement of a place east or west of the prime meridian This meridian is also known as the Greenwich Meridian because it runs through the original site of th
87. ms abbreviations and selected terms used in SiRF documentation SiRF Demo User Guide June 2007 vii Troubleshooting Contacting SURF Technical Support Address SiRF Technology Inc 217 Devcon Drive San Jose CA 95112 U S A SiRF Technical Support Phone 1 408 467 0410 9 am to 5 pm Pacific Standard Time Email support sirf com General enquiries Phone 1 408 467 0410 9 am to 5 pm Pacific Standard Time Email gps sirf com Helpful Information When Contacting SiRF Technical Support Receiver Serial Number Vill SiRF Demo User Guide June 2007 Supported Products SiRFDemo User Guide June 2007 Overview Ji The SiRFDemo software is a tool that provides real time monitoring of an attached GPS receiver s operation such as satellites being tracked observed signal strength and current position It also provides the ability to configure the receiver for specific operating modes as well as a data logging ability for later investigation See Chapter 3 Using the SiRFDemo Software for detailed information on the use and operation of the SiRFDemo software The SiRFDemo software supports multiple product lines and different software releases Available features of SiRFDemo may be different available or not available depending on the GPS product being used Supported GPS products include e GSW2 SiRFXTrac SiRFNav SiRFDRive GSW3 GSWLT3 e SiRFDiRect e SiRFInstantFix Extended
88. n SiRF Binary msg 0x38 or OxE8 is received on the Main serial port it is forwarded to the Aux port and logged in the gps log file as GPS gt CLM TCP instead of Serial Port Option The main data source can be configured as a TCP IP connection instead of a serial port This is useful when the test setup is SD lt gt CLM lt gt Rx and the connection between the CLM and Rx is a physical serial port while the SD to CLM connection is TCP To do this select TCP 7555 from the Aux Data Source Port dropdown menu Data Source Setup SerialPort TCP 7555 Baud Rate 57600 x Cancel Cle 0 C Random Virtual Serial Port Data Piping Create Virtual Serial Port Port Protocol Aux Data Source Use Aux Data Source Port Baud Rate SiRFDemo User Guide June 2007 3 The number 7555 is the port that is used on your local host machine IP 127 0 0 1 in this case 7555 is the default port for the CLM test app Note that the log file contains two new messages when logging TCP data Any data sent is logged as TCPx OxAQA2 instead of Tx OxAOA2 When TCP data is received a TCP data len message is logged showing the number of bytes received over TCP Virtual Serial Port Data Piping Using the SiRF Demo Software The user has the option of creating a virtual serial port for piping serial data to an additional application The use of this functionality is optional If an external virtual s
89. n only to SiRFDRive Error View 10 255 SiRF Binary message 10 error codes are converted to human readable strings message 255 strings flagged as errors are displayed in this window instead of the debug view window Message 255 for the Aux Output View pertains only to SiRFDRive Output View All Messages This view displays each message ID received in both decimal and hex along with 0 255 the SiRF Binary message name for that message ID Message 255 pertains only to SiRFDRive DGPS View 27 50 MID DGPSStatus 27 MID SbasStatus 50 Message 27 pertains to all software except SiRFXTra Messages 50 pertains only to GSW2 SiRF Demo User Guide June 2007 A 1 A 2 Window Name Geodetic Nav View PPS Timing View Aux Output View Ephemeris Info View SiRFDRive Status View SiRFDRive Sensor View SiRFDiRect Graph View Table A 1 SiRFDemo View Window Continued Messages 41 32 I S 30 56 48 48 172 li Comments Some additional fields are displayed for SiRFDRive Reverse Flag or Fusion Map Matching GPS receiver software under test MID_PPS_Time 52 Message 52 pertains only to GSW2 MID DrIn 172 MID ASCIIData 255 this is not only message 255 but can be any text data received on the aux data source channel This window is specifically designed for SiRFDRive 2 development Messages 172 and 255 pertain only to SiRFDRive Messages used are clearly indicated in the display window for message 56 sev
90. nd retains all other data SiRFDemo User Guide June 2007 Uo Hi Table 3 13 Reset Options continued Reset Mode Description Warm w Init Clears all initialization data in the board and updates the data that is entered in the Initialization screen The almanac is retained but the ephemeris is cleared Cold Clears all data that is currently stored in the internal memory of the board including position almanac ephemeris and time The stored clock drift is retained Factory Reset Clears all data including position almanac ephemeris time and stored clock drift All board parameters are also set back to factory defaults 2 When selecting Warm w Init reset mode enter the Latitude Longitude Altitude and Heading for the current position of the GPS receiver 3 Click Send to send the command Initializing SiRF XTrac 3 0 amp 3 1 and 3 2 Navigation Parameters When SiRFXTrac 3 0 amp 3 1 or 3 2 are selected from the Setup SW menu the Receiver Initialization screen offers the additional options described below Messages if Enable Nav Lib Data iw Enable Debug Data GPS Only Reset System Reset This also clears User Ham Disable Broadcast Eph Messages if Enable Nav Lib Data iv Enable Debug Data GPS Only Reset System Reset This alzo clears User Ham SiRFXTrac and 3 0 amp 3 1 The 3 2 reset options reset options located in located in the botto
91. ng From 03 26 11 PM 10 02 2003 to 09 26 11 PM 10 02 2003 AE 3 33 3 34 Each of the available message types and a brief description is provided in Table 3 11 Table 3 11 Messages That Can Be Logged to a File Messages Description 001 Ref Nav undefined 002 Measured Navigation 004 Measured Tracking 005 Raw Track Data 006 SW Version 007 Clock Status 008 50 BPS Subframe Data 009 Throughput 010 Error 011 Command Ack 012 Command Nak 013 Visible List 014 Almanac 015 Ephemeris 017 Raw DGPS 019 Revr Params 027 DGPS Status 028 Nav Lib Meas 029 Nav Lib DGPS 030 Nav Lib SV State 031 Nav Lib Init 041 Geodetic Nav 045 ADC ODO 046 Test Mode 048 SiRFDRive 050 SBAS Status 052 PPS Timing 055 Test Mode 4 Trk Data 056 SEA Output 172 Wheeltick Reference Navigation Time position velocity Satellite status and C No Not supported by SiRFstarlI Software version of the connected GPS receiver Board clock performance Satellite ephemeris and almanac data CPU throughput usage Various error messages Acknowledgment of received commands Input message failures Satellite visibility list based on current almanac Satellite almanac data Satellite ephemeris data Differential GPS corrections in RTCM format Parameters affecting navigation solutions Status of differential GPS correction Observed satellite measurement data Received differential GPS correction information Observed v
92. ng GPS satellites the Signal Level Tracking and Map views display information about the current operation of the receiver VSiRFDemo Setup View Action Navigation Poll Window meS leng g m View SiRF Binary 0 Radar View ag GPS Time 269600 00 Week 340 f66100Predg ee ags 100 Clk 0 00 4 Lat 37 37599 Hdg 353 NLC 22 1 Respons iS Sel K3 Lon 121 91448 Vek 0 440 k Week1364 TOW 26959199 aq DE B SH Fix Validated Alt 49 Clock Drift 95572 Hz Clock Bii Er E 6 SVs Used in Fix 22125111413 NG Week 1364 TOW 26959299 EL Clock Diit95572 He Clock Bid Rx Ephemeris for SV UZ a d week 1364 TOw 26959400 F M Ephemeris for SY TE ell Clock Drift 95572 Hz Clock Bigg 27M CPnemenis tor sy E Week 1364 TOW 26959499 F M Ephemeris for SY 07 Clock Drift 95572 Hz Clock Big H M Ephemeri for SV 1C j Week 1364 TOW 26959599 R M Ephemeris for SY 1 Clock Drift 95572 Hz Clock Bid R M Ephemeris for Week 1364 TOW 26959699 RM Ephemeris for SV 1E a Clock Drift 95573 Hz Clock Big P M Ebhemeris for SV 21 ei Week 1364 TOW 26959799 ff R M Ephemens for SY 2 Clock Drift 95573 Hz Clock Big 2M Ephemeris for SV 2E al Week 1364 TOW 26959900 hash creer fa Sa Clock Drift 35573 Hz Clock Big cE Week 1364 TOW 26960000 Comm oag Bad parity from S 22 sut Clock Drift 95573 Hz Clock Bid Ba d party from SV 01 sub EET PE NP Ron pe ce For detailed information about each of the v
93. nse Time 0 255 sec Max Requested Horiz Error 20 Meters Max Requested Vert Error No Maximum Accuracy Priority Preference NoPreterance Setting the Message Rate You can configure each SiRF binary output message so that it is output using a specified frequency To set the SiRF binary output rates 1 Select Set Message Rate from the Action Menu The Message Rate screen is displayed Message Rate j X Message name 0x01 True Navigation Message update rate o range D 30 Cancel Send Message Now SiRFDemo User Guide June 2007 3 2 Select the appropriate SiRF binary message from the Message name dropdown menu 3 Enter the rate at which you want the selected SiRF binary message to be output 4 Check the Send Message Now checkbox to send the message now 5 Click Send Note The message rate is based on navigation cycles not seconds For example in TricklePower mode at an update rate of two seconds selecting five as the message output rate outputs the selected message every Ten seconds Ten seconds in this case is equivalent to five navigation cycles An Update Rate of zero disables the output of that message The decrement of the navigation cycle counters for each message begins when the GPS receiver accepts and verifies the input command Each message is done separately and no mechanism is currently in place to synchronize message output Message counters are stored in DRAM so
94. o 2 Select the required operating parameters Description Default SBAS When set to Auto Scan the GPS receiver automatically searches for and use Auto PRN any available SBAS correction source Otherwise it only uses corrections Scan from the SBAS source identified by the PRN entered in the PRN field Mode Used to indicate the current operating mode of the SBAS system being Testing used The operating mode is displayed in the DGPS View screen See The DGPS View Screen on page 3 17 Timeout When set to default the timeout as provided by the SBAS system is used Default Source this is typically 18 seconds When User Defined is selected the timeout value as set by the DGPS Mode dialog is used See Setting the DGPS Mode on page 3 61 3 Click Send to accept the settings The Poll Menu This section describes the SiRFDemo software functions under the Poll menu eles SiRFDemo setup View Action Navigation fEng Window malm e nlg Aux Output View g oi Version Clock Status Mav Parameters Almanac Ephemeris Ephemeris State Extended Ephemeris e Polling the Clock Status on page 3 65 e Polling the Navigation Parameters on page 3 66 e Downloading an Almanac File on page 3 67 e Downloading an Ephemeris File on page 3 68 e Polling the Ephemeris State on page 3 68 e Polling the Extended Ephemeris on page 3 69 3 64 SiRF Demo Use
95. of the serial cable to Com A on the GPS receiver Connect a power supply to the GPS receiver and power it on SiRFDemo User Guide June 2007 NI ll Quick Start The following provides instructions on getting SiRFDemo started and operating correctly with a SiRF based GPS product To get started quickly 1 Connect the GPS receiver to your PC using the provided serial cable and power on the receiver For more information about installing the GPS receiver please see the associated Users Guide 2 Double click on the SiRFDemo shortcut on your desktop that was created during the install process SiR FDemo The Data Source Setup screen is displayed Data Source Setup f Serial Port COM Baud Rate 57600 Cancel Ca cwm Binary z C Random Virtual Serial Port Data Piping Create Virtual Serial Port Port Frotoc ol Sux Data Source Use 4us Data Source Port Baud Rate 3 Select the PC serial port that is being used from the Serial Port pull down list and the baud rate the receiver 1s operating at from the Baud Rate pull down list Note SiRFDemo only displays a list of available serial ports When USB is being used the USB port is listed as an additional serial port 4 Click OK By default the Signal Level Tracking and Map views are displayed 5 Click the Connect Disconnect button Getting Started 2 5 When your GPS receiver is properly connected and tracki
96. om the dropdown menu 3 Click Send to reset the GPS receiver and computer serial port to start communicating using the new Baud rate 3 44 SiRF Demo User Guide June 2007 Uo Hi Setting the DGPS Serial Port Parameters The Set DGPS Serial Port Parameters function configures the second serial port the serial port not currently used by the SiRFDemo software of the attached GPS receiver for reception of RTCM data To configure the available port for RTCM reception 1 Select Set DGPS Serial Port from the Action menu The Set DGPS Serial Port Parameters screen is displayed x BaudRate 3600 e a A Data Bits o S ance Parity NONE Stop Bits ji 2 Select the Baud rate data bits parity and stop bits for the DGPS serial port parameters from each dropdown menu 3 Click Send to reset the connected GPS receiver and change the protocol of the second port to RTCM and the serial port settings to the selected values Note The differential correction data source must be configured separately See Defining the Data Source on page 3 3 Setting the UART Configuration Using the SiRFDemo Software The UART configuration control is supports four unique UARTS You can configure UART settings such as protocol Baud rate data bits parity and stop bits using the UART configuration control The UART configuration control is provided primarily for system developers Even though control over four UARTs is p
97. on 0 Center point is directly overhead Eleyation 90 True and Measured Position Information Arrowhead represents true direction of travel and velocity where the outer circle represents the velocity entered below and the inner circle is half that Outer circle velocity i o res epesente the measured direction of travel and position where tre outer ciele repesente the distance entered below and tHe rer Circle ts hali that Dinter ciee position 20 m 2 Select the direction of the tracking orientation that you want to use Description North Up True north points to the top of the circle Heading Up This option can be used when driving Current heading points to the top of the circle 3 Enter the Outer circle velocity in m sec Note The setting of the outer circle velocity means that when the arrow length reaches the outer circle of the plot then the outer circle velocity has been reached 4 Click OK to save the changes or Cancel to exit without saving changes The Map View Screen The Map view screen displays a combination of graphical and text based information Positions generated by the GPS receiver are plotted on the Map view screen while other information such as GPS time GPS week position mode current position heading velocity DOP type of position fix and satellites tracked are displayed as text To display the Map view screen SiRFDemo User Guide June 2007 Oo IH Ea
98. or Message View screen 1s used to display any error messages that the GPS receiver may generate Error messages are generated automatically by the GPS receiver under certain conditions Many are caused by normal GPS operations such as acquiring a low elevation satellite which could result in a bad parity To view the Error Message View screen 1 Select Messages Error from the View menu The Error Messages View screen 1s displayed REE Bad parity from SY 7 subframe Bad parity from S 01 subframe 0 Bad parity from 54 08 subframe 0 Bad parity from S 31 subframe Bad parity from S 8 subframe Bad parity from 54 03 subframe 0 Bad parity from SY 22 subframe 0 Bad parity from SY 20 subframe 0 SiRFDemo User Guide June 2007 Oo Hi The Debug Data View Screen The Debug Data View screen displays additional information about the GPS receiver operation The data is generated automatically by the GPS receiver To view the Debug Data View screen 1 Select Messages Debug from the View menu iol xi ETime 00000014 Int 0067 006 005 mg 0231 BF BF BF BF BF BF BF BF OO 00 DO 00 1000 a Adjust MaAy gt swtow 24r 530 065756 clkb 0 000713 gpstowest 247530 065043 BufkallocF alure 0 avail buffers 66 Increment OldT OW 247530 065756 OldT ag 15000 HewT OW 247531 065756 NewT ag ETime 00000015 Int 0067 006 006 ms 0232 BF BF BF BF BF BF BF BF OO 00 00 00 1000 CSTO Ne
99. osition is calculated Off Degraded Mode Timeout The GPS receiver only operates in any degraded mode for the period 30 of time specified by the timeout Dead Reckoning Enable Dead When a position solution is not possible due to insufficient satellites On Reckoning a positions is calculated using the last known velocity Only applies Mode when the GPS receiver is being used in a dynamic environment Timeout The GPS receiver only calculates positions using dead reckoning for 5 the period of time specified by the timeout 3 Click Send to accept or Cancel to exit 3 58 SiRF Demo User Guide June 2007 Setting the DOP Mask Control Uo Hi This mask enables you to control the position output of a GPS receiver so that positions computed with a high DOP value are not output When the DOP mask is exceeded the position message status changes to DOP mask exceeded and the position does not update To set the DOP mask controls 1 Select DOP Mask from the Navigation menu The DOP Mask screen is displayed DOP Mask Default X C Auto PDOP HDOP T Use PDOP ony Threshold f0 Cancel C Use HOOF only Threshold l0 C Use GDOP only Threshold lo Do not use 2 Select the Mode that you want to use Description Default Auto PDOP HDOP The PDOP mask is used when four or more satellites are Off available When only three satellites are available the HDOP mask is used Use PDOP only Only the PDOP mask is used regardless of t
100. plete a shortcut is placed on your desktop and within the Start Programs menu To install the software tools without using the CD browser 1 Insert the CD into your CD ROM drive 2 Using Windows Explorer navigate to the folder of the software tool you want to install 3 Double click on the file SETUP EXE An install shield guides you through the rest of the installation Note During the install process USB driver files are copied into the SiRFDemo directory These files are required when USB communication is used Additional installation of the drivers are required after installing SiRFDemo SiRFDemo supports USB communication Before USB can be used however it is necessary to install the required UBS drivers These drivers have been copied to the SiRFDemo directory during the installation process of SiRFDemo The install process for the USB drivers is different for different operating systems Note When USB is being used the USB port is listed as an additional serial port in the Data Source Setup dialog SiRF Demo User Guide June 2007 NI ll Windows XP Installation To install the required USB drivers on Windows 2000 l Connect the USB enabled SiRF GPS receiver to your PC Windows opens a Found New Hardware Wizard window Select Install from a list or specific location Advanced and press Next Select Include this location in the search Press Browse to locate the dire
101. r Guide June 2007 Uo Hi Viewing the Software Version Polling the Clock Status Using the SiRFDemo Software The poll software version function allows you to query a GPS receiver for the version of embedded software currently being run To view the current software version 1 Select SW Version from the Poll menu The Response View screen is displayed showing the software version currently being run Response View Week 1365 TOW 34062599 E3tGP5 Time 340625999 me SY Cnt11 Clock Drift FB Hz Clock Blas 2b5b 362 ne Sty VETS Ta IH GS ay Na Paki O aki 4 1 0 10 ace 33P1 IC Acknowledged MID PallS wVersion The poll clock status function allows you to query a GPS receiver for clock performance information including the GPS week number GPS time clock drift and clock bias To poll a GPS receiver for clock status information 1 Select Clock Status from the Poll menu The Response View screen is displayed with the clock status Response View L fox Ack nowledged MIC Fo HIE Ie uk Status l Week 1365 TOW 34107899 EstGPSTime 341078999 ms SYCnk3 Clock Drift 95605 Hz Clock Bias 5407 3261 ns Week 1365 TOW 34107999 EstGP5Time 341079555 ma 5WCnk 10 Clock Drft 95605 Hz Clock Bias 54133950 ns Week 1365 TOW 34109299 EstGFS Time 341092999 ms 5YEnt10 The following table provides a description of the clock status items Description Week TOW EstGPS Time SVCnt Clock Drift
102. rallel Receiver PDOP Pi P P PPS Acronyms and Abbreviations Glossary A HI Million Instructions Per Second a measurement of the speed of a computer Megahertz a unit of frequency equal to one million Hz Most Significant Bit within a binary word Mean Sea Level Mean Time Between Failures Memory Upper Lower a control line on SiRF baseband chips used to select part of a memory word GPS positioning errors caused by the interaction of the GPS satellite signal and its reflections Millivolt Milliwatt North East Down coordinate system See LTP The data added to the GPS satellites PRN codes The navigation message is composed of data bits sent at 50 bps Data words consist of 30 consecutive bits and contain 24 bits of actual data and 6 bits or error detection codes A group of 10 consecutive words are called a subframe 5 consecutive subframes are called a frame 25 consecutive frames are called a super frame The 5 subframes that form a frame contain the transmitting satellite s ephemeris and clock correction in the first 3 subframes and system information such as satellite almanacs in the remaining 2 subframes Noise Factor National Marine Electronic Association Also commonly used to refer to NMEA 0183 Standard for Interfacing Marine Electronic Devices a serial message protocol commonly used by GPS receivers Non volatile Random Access Memory portion of the SRAM that is powered by a backup battery power suppl
103. represented by color see Table 3 4 Table 3 4 Tracking View Color Coding Color Description Red The satellite location is know from almanac information however the satellite is not currently being tracked Blue The satellite is being tracked however it is not being used in the current position solution Green The satellite is being tracked and is being used in the current position solution Aqua For SBAS satellites only The satellite is being tracked and corrections are being used in the current position Magenta The satellite is being tracked however a SiRFInstantFix extended ephemeris is being used for the position solution Current speed and heading in a dynamic environment such as a moving vehicle is represented by an arrow The direction of the arrow represents heading while the length of the arrow indicates speed over ground Using the SiRFDemo Software 3 1 3 12 Configuring the Radar View Screen The Radar view screen orientation and velocity representation can be configured To configure the Radar view screen 1 Double click the Radar View screen to display the Tracking View Configuration screen Tracking Yiew Configuration l X Satellite Information Green Satellite with lock used in calculation Cancel Blue Satellite with lack not used Orientation North Up Heading Up Red Satellite without lock not used Outer circle represents the horizon Elevati
104. rovided most products only support two UARTs 3 45 IH Oo To set the UART configuration of the attached SiRF GPS product for the two supported UARTs 1 Select Set UART Configuration from the Action menu The UART Configuration screen is displayed UART Configuration Note The COM ports supported in a standard GPS receiver are UART 0 CPU SCIO 0 COM A and UART 1 CPU SCIO 1 COM B 2 Check the Set checkbox for each UART you want to apply changes to When the Set checkbox is not checked the existing configuration remains in its current state 3 Select SIRF binary NMEA RTCM or No I O from the Protocol selection list Select No I O from the Protocol dropdown menu to disable the data output from any port Each protocol can only be supported by one UART You cannot configure two different ports to use the same protocol 4 Select the appropriate serial communication parameters using the selection lists for Baud rate data bits parity and stop bits 5 Click Send to accept or Cancel to exit 3 46 SiRF Demo User Guide June 2007 Uo Hi Uploading an Almanac to a GPS Receiver An almanac file is used by a GPS receiver to assist with locating and tracking available satellites When a current almanac file does not exist in the GPS receiver due to a cold start or when it is not used for a long period of time loading a recent almanac file assists the GPS receiver in locating and tracking satellites To upload an
105. s 6 Open the external application and choose the created virtual serial port as the data input port Changing Preferences You can change the appearance of some of the view windows to suit your personal preferences View preferences include the Signal Level view the Tracking view and the Map view To change the appearance of the view windows 1 Select Preferences from the Setup menu The Preferences screen is displayed x Signal Graph Type Bar C Line Save ii Cancel Tracking Orientation t North Up C Heading Up Map View 0 3 meters per pixel 2 Select the type of signal graph that you want to view on the 12 Channel Signal Level View screen Description Bar Displays the data with vertical bars to represent the observed signal strength of each satellite Line Displays the data in a continuous line graph form 3 Select the direction of the tracking orientation that you want to use in the Tracking View screen Option Description North Up True north points to the top of the circle Heading Up This is typically used when the board is moved by simulation Again it is not recommended to use the board in a vehicle Current heading points to the top of the circle 4 To change the scale of the Map view enter the number of meters you want each pixel to represent in the Meters Per Pixel field 5 Click Save to save the changes or Cancel to exit without savin
106. s GPS Week GPS week number SiRF Demo User Guide June 2007 Uo Hi Table 3 5 Navigation Message View Information continued Information Displayed Description DOP Dilution of Precision Fix Validated unvalidated From an unvalidated state a five SV position solution must be achieved to become a validated position If the board continues to navigate in a degraded mode 3D 2D ISV or DR then the validated status remains When navigation is lost completely an unvalidated status results Time Current GPS time seconds SVs Used in Fix SV PRN used in solution Time To First Fix The TTFF value is cleared any time a no nav position is reported msg 2 so the TTFF field is automatically cleared when a reset command is sent 1 The Mode field is mapped to SiRF Binary Protocol MID2 mode 1 see the SiRF Binary Reference Manual The mode field should be used as the TTFF indicator and not the Fix field with any non zero value of mode 1 indicating a usable navigation solution 2 The Fix field is mapped to SiRF Binary Protocol MID2 mode 2 see the SiRF Binary Reference Manual Note ECEF XYZ is converted geodetic latitude longitude and altitude based on the WGS84 ellipsoid parameters The Response View Screen The Response View screen is used to display any response to a poll request You can poll the GPS receiver for the software version see Polling the Extended Ephemeris on page 3 69 on page 3 64 c
107. s described in the following table Table A 1 SiRFDemo View Window Window Name Messages Comments Signal View 2 4 30 Message 4 describes everything except the blue green color distinction which is based on SVs used in the navigation solution from message 2 and green magenta color distinction based on the extended ephemeris flags from message 30 Message 30 pertains to all software except SiRFXTrac Radar View 2 4 30 Message 4 describes everything except the blue green color distinction which is Map View 2 41 Navigation View 2 41 based on SVs used in the navigation solution from message 2 and green magenta color distinction based on the extended ephemeris flags from message 30 Message 30 pertains to all software except SiRFXTrac Message 2 describes everything except message 41 which is used for the heading field when SiRFDemo is configured for SiRFDRive Message 2 describes everything except message 41 which is used for the heading field when SiRFDemo is configured for SiRFDRive Debug View 255 and All Displays the text from SiRF Binary debug messages MID 255 and displays NMEA Messages NMEA text messages when available Response View 6 7 11 12 19 MID SWVersion 6 MID ClockStatus 7 MID_Ack 11 MID_Nak 12 45 48 MID RxMgrParams 19 with subid O for regular nav subid 1 for APM nav MID_TrkADCOdoGPIO 45 MID DrOut 48 with subids 5 for DrValid 6 for GyrFactCal and 7 for DRSensParam Messages 45 and 48 pertai
108. s multiple product lines and different software releases These include GSW2 GSW3 GSWLT3 SiRFNav SiRFDRive SiRFDiRect SiRF InstantFix Extended Ephemeris and SiRFXTrac A built in auto detection feature 3 1 3 2 allows SiRFDemo to identify the hardware software platform it is connected to and configure the dropdown menus correctly This provides access to features that are common to both platforms such as protocol and individual access and definition to features that are either unique such as Static Navigation or redefined such as TricklePower for each platform Once connected SiRFDemo attempts to identify the connected product and software release When the hardware detection function fails you are prompted to select the target software manually The auto detection function can be disabled by unchecking the Auto detection checkbox To select the target software type 1 Select Target S W from the Setup menu The Select Target Software dialog is displayed Select Target Software Ed Target GSW 23 or higher GoW P1622 Cancel Gow 2 0 SIRFOR We 1 8 amp 2 8 SIRF ay SIRF Trac SIRF avDR GSW 3 0 amp 3 1 GSWLTS 2 GSM 3 2 or higher SIRFO Rect Oehee eee Auto detection 2 Select the appropriate target software 3 Uncheck the Auto detection checkbox to disable the auto detection function or when the auto detection fails 4 Click OK to accept the selection GPS Time PC Time The SiRFDemo soft
109. sages or Cancel to abort opening a file During logging logging status is displayed at the bottom of the SiRFDemo screen Logging from 03 26 11 PM 10 02 2003 to 04 26 11 PM 10 02 2003 d 3 36 SiRF Demo User Guide June 2007 Uo IH Pausing the Display in All of the open windows can be paused to allow easy viewing of the existing data without receiving any further data To pause all of the open windows 1 Click the Pause button or select Pause Display from the Action menu Note No data is logged while the display is paused Initializing the Data Source Ce Using the SiRFDemo Software You can reset or initialize a connected GPS receiver directly through the SiRFDemo software This function may be used to demonstrate or evaluate a product s recovery ability under different circumstances The Receiver Initialization screen offers additional features depending on which target is selected in the Setup Target SW menu When SiRFDrive is selected in Setup Target SW menu see Initializing SiRFDRive Navigation Parameters on page 3 40 When SiRFXTrac 3 0 amp 3 1 or 3 2 is selected in Setup Target SW see Initializing SiRFXTrac 3 0 amp 3 1 and 3 2 Navigation Parameters on page 3 41 To perform a reset or allow Nav Lib or Development data to be output from a receiver 1 Click the reset button or select Initialize Data Source from the Action menu The Receiver Initialization screen
110. satellite signals it can compute a solution without having to learn the ephemeris from the satellite navigation messages The knowledge of approximate time and position permits the receiver to search for those satellites that are known to be visible from the receiver s position Hertz a unit of frequency cycles per second Input Output Intermediate Frequency Interrupt ReQuest line Interrupt Service Routine International Geomagnetic Reference Field Issue Of Data Clock a reference value in the navigation message that indicates the version of clock corrections C 3 IH A IODE Kalman Filter km L1 L2 Latitude LLA LNA Longitude LPTS LSB LTP m s m s s or m s m s s s or m s Mask Angle MID C 4 Issue Of Data Ephemeris a reference value in the navigation message that indicates the version of orbital parameters IODE is a subset of IODC Joint Program Office An office within the U S Air Force Systems Command Space Systems Division The JPO is responsible of managing the development and production aspect of the GPS system and is staffed by representatives from each branch of the U S military the U S Department of Transportation U S Defense Mapping Agency NATO member nations and Australia Sequential estimation filter that combines measurements of satellite range and range rate with the last computed position to determine the position velocity and time at the GPS receiver antenna Kilo
111. sible tracking status messages and the corresponding tracking status Each tracking status state corresponds with an achieved tracking stage for each channel of the GPS receiver For example when a tracking status of 33 Hex is displayed this means that satellite acquisition is achieved the delta phase is valid the carrier pull in is complete and the code is locked onto From a cold start you typically see the following sequence of tracking status changes 0033333733F BF It only takes about one second to achieve a 37 status approximately another 12 seconds to get to a 3F status and finally another 20 seconds to achieve a BF status The sequence and time frames may vary considerably between channels and sessions Table 3 2 Tracking Status Definitions Achieved Tracking Stage r rn Tracking sa B 5 os Be a a Status EN SX lo P2 22 a 52 2 3 Hex a a ons Sg AR z8 4s 217 00 01 v 03 V ix 21 v v m 7 ele M P v 7 p 7 v sy la pm V v lv V ki la V lv a Y lv v ly v m ig isfy ivy la lx Using the SiRF Demo Software 3 9 3 10 Table 3 2 Tracking Status Definitions continued Achieved Tracking Stage E a 2 S z D 2 2 S 35 1a e Tracking 22 2 5 s E8 2 2 By an as 55 32 FS 22 K5 53 Fs Hex HA lt i O nj O A N N sa Sp tn AG VI VA V lv v V V V V V V AF a v v iv lv v v v 40 v a Z Iy v iv on Y Iy v iv v
112. sing the SiRFDemo Software The Geodetic Nav View screen is displayed i Geodetic Nav View E O8 Nav Validity Valid Nav Mode 3d GPS Wk 1365 TOW 34452 9599 sec UTC 2006 03 08 23 08 27 999 06 Svein Fe 39141519 22 Lat 37 3794562 deg Lon 121 9147974 deg Altfellip 6 44 m Alfmal 34 01 m Map Datum 21 HOOF 1 2 SOG 0 34 msec Hdg 52 45 deg Mag Yar 0 00 deg Cimb Ate 0 05 m sec Hdg Rte 0 00 deg zec EHPE 2 37 m EWPE 3 34 m ETE 0 00 rn EHVE 0 00 m sec Clk Bias 6004 35 14 m Error 0 00 rn Clk Ort 18192 84 msec Error 0 00 rn Traveled 0 rm Error O r DR Direction M A Map Matching Feedback Input N44 Map Matching Feedback Revd M A Map Matching Feedback Used in Solution NAA Hdg Error 0 00 deg The following table provides a description of each of the displayed items Table 3 6 Geodetic Nav View Screen Displayed Items Information Description Nav Validity Provides navigation validity When the navigation solution is not valid the reason for this are displayed Nav Mode The current mode of the navigation solution GPS Wk The GPS Week TOW Time of Week in seconds UTC UTC time SVs in Fix The number of satellites currently used in the navigation solution Lat The current calculated latitude in degrees Lon The current calculated longitude in degrees Alt ellip The altitude above the ellipsoid in meters Alt msl The alt
113. t value is exceeded or a new differential correction is received 4 Click Send to accept or Cancel to exit Note For a differential position to be calculated there must be pseudorange corrections for every pseudorange used in the solution When pseudoranges are without corrections and the GDOP improves by two by using all pseudoranges the solution does not use available corrections Selecting the DGPS Source Many SiRF products have the ability to receive RTCM differential corrections from different sources The DGPS source control is used to select which source is used to obtain RTCM differential corrections To select the DGPS source 1 Select DGPS Source from the Navigation menu The DGPS Source screen is displayed DGPS Source Default X Cancel Source C None C SBAS channel ii External RTCM data serial port B C intemal GPS beacon receiver Internal CGPS beacon receiver Auta scar I Frequency Hel Bitrate 6ps 100 SiRFDemo User Guide June 2007 2 Select the Source that you want to use Oo Hi Description Default None The GPS receiver does not use any of the available DGPS sources No SBAS Channel The GPS receiver uses the SBAS correction service when available No One of the twelve channels 1s dedicated to the SBAS signal External The GPS receiver uses any RTCM corrections that are input Yes RTCM Data directly through one of the serial ports Internal DGPS The internal
114. tellite Elevation SEP Sequential Receiver SNR SPI SPS SRAM SSP SV C 6 PseudoRandom Number The identity of the GPS satellites as determined by a GPS receiver Since all GPS satellites must transmit on the same frequency they are distinguished by their pseudorandom number codes which range from to 32 The calculated range from the GPS receiver to the satellite which is determined by measuring the phrase shift of the PRN code received from the satellite with internally generated PRN code from the receiver Because of atmospheric and timing effects this time is not exact Therefore it is called a pseudorange instead of a true range Position Velocity and Time Random Access Memory a form of computer memory that may be read and written to by the processor A GPS receiver specification that indicates the number of independent hardware signal processing channels or unique tracking resources included in the receiver design Radio Frequency Radio Frequency Interference Read Only Memory a form of computer memory that may be read by the processor but not written to real time Clock A private not for profit corporation that develops consensus based recommendations regarding communications navigation surveillance and air traffic management CNS ATM system issues Previously called Radio Technical Commission for Aeronautics The Radio Technical Commission for Maritime Services an organization that sets stand
115. til Ack is Revd is checked then SiRFDemo sends the disable broadcast eph msg every 1 second until the ack is received from the receiver at which time the disable broadcast eph every second checkbox becomes unchecked The second section displays the contents of the client s T message request for ephemeris from the CLM When a T message is received in SiRFDemo it records the PC time of the event and shows a timer indicating the time elapsed since the last T message was received Clear clears the display for this section of the window The Eph field from msg 30 for each SV that is reported This section only updates when the receiver s NavLib output is enabled To enable NavLib output send a snap start with the nav lib option checked Clear clears the display for this section of the window The response messages to a poll ephemeris state message are shown in a table of SVIDs vs 5 fields ephemeris flag eph week num TOE time of week in 16 second increments Integrity of ephemeris and Age if an extended ephemeris is used Poll sends SiRF Binary msg OxE8 subId 0x02 with SvMask OxFFFFFFFF which requests the ephemeris state for all SVs 1 32 Note Poll has the same effect as selecting Poll Ephemeris State Clear clears the display for this section of the window Note The response messages fields may contain either broadcast ephemeris data or extended ephemeris data SiRF Demo User Guide June 2007 The Act
116. ts aana B 2 THOS CA B 2 POSTE on 54 46646455 PE PA B 4 pada AA B 4 Pa CA PAA B 4 PO Hao 2s teen E we see nee eee enka oewe ees EE B 4 C Acronyms and Abbreviations Glossary C 1 SiRF Demo User Guide June 2007 Preface The SiRFDemo User Guide contains detailed information about how to use the software tool called SiRFDemo This User Guide is based on SiRFDemo release version 3 87 but may be relevant to later versions Who Should Use This Guide This manual was written assuming the user has basic computer skills and is familiar with the Windows operating environment How This Guide Is Organized Chapter 1 Overview gives a high level overview of the SiRFDemo software product including what it does supported products and available menus Chapter 2 Getting Started explains how to install the software and hardware how to start the SiRFdemo software basic operation and how to ensure that the software and the GPS receiver are operating correctly Chapter 3 Using the SiRF Demo Software describes SiRFdemo menu functions Appendix A SiRFDemo Real Time View Windows lists supplimental information about message content in the SiRF real time view windows Appendix B File Formats describes the format of files that are either used by the SiRFDemo software or are created by the SiRFsig software Appendix C Acronyms and Abbreviations Glossary describes all acrony
117. w almanac for 5 Y 1 Adjust Aw sutow 247531 065756 clkb 00000764 gpstowest 247531 064992 BufkallocF allure 0 avail buffers 66 NTSC Crt 5 Increment OldT O 247531 065756 OldT ag 16000 NewT OW 247632 065756 NewT ag ETime 00000016 Int 0067 006 005 ma 0236 BF BF BF BF BF BF BF BF OO 00 0000 1000 Adusia swtow 2475392 065756 clkb 0 000815 gpstowest 247537 06494 BukallocF alure 0 avail buffers 66 a Note To view incoming debug data the Enable Debug Data checkbox must be enabled on the Receiver Initialization screen See Initializing the Data Source on page 3 37 The DGPS View Screen Using the SiRFDemo Software Depending on the target software choices of DGPS operation include SBAS external RTCM or Internal DGPS Beacon See Selecting the DGPS Source on page 3 62 for more information about each of these options The DGPS View provides information about the DGPS source and current operation To view the DGPS View screen 1 Select Messages DGPS from the View menu 3 17 3 18 The DGPS View screen is displayed 01x SAS channel 1 5 15 a 4 42 13 A 72 16 3 91 20 3 25 ee E17 0 00 0 0 00 0 0 00 0 0 00 T T 0 00 0 00 GPS corrections PAN Correction m Age z Internal DGPS beacon receiver Locked Frequency kHz Bit Hate bpa Signal Magnitude Signal Strength JB 124 WAAS auto Mo
118. ware is capable of matching GPS clock time to PC time When the difference between GPS time and PC is greater than two seconds PC clock is set to match GPS time To select GPS Time PC Time 1 Select GPS Time PC Time from the Setup menu SiRFDemo User Guide June 2007 Oo IH The Setup menu is displayed 1SiRFDemo DSR view Action Navigation Poll Window Target SAN sl Data SOUrce GPS Time gt PC Time When a checkmark appears next to GPS Time the clocks are matched Defining the Data Source The SiRFDemo software is capable of receiving data from different sources You can configure SiRFDemo to receive data directly from a connected GPS receiver generate its own random data or load data from a previously logged file To configure the source of the data used by the SiRFDemo software oe 1 Click the Data Source button or select Data Source from the Setup menu The Data Source Setup screen is displayed Data Source Setup Serial Port COM1 Baud Rate 57600 Cancel Crile 0 C Random Virtual Serial Port Data Piping Create Virtual Serial Port Pott Protocol Aux Data Source Use 4ux Data Source Pott Baud Rate 2 Select either the Serial Port File or Random as the required data source The following table provides a description of each available option Description Serial Port SiRFDemo uses data directly from a connected GPS receiver The
119. y when prime power is removed It is used to preserve important data and allow faster entry into the Navigation Mode when prime power is restored Term used to describe periods of time during which a GPS receiver s line of sight to GPS satellites is blocked by natural or man made objects Original Equipment Manufacturer The solution of a system of equations containing more equations than unknowns The GPS receiver computes when possible an overdetermined solution using the measurements from five or more GPS satellites instead of the four necessary for a three dimensional position solution Precise Code A spread spectrum direct sequence code that is used primarily by military GPS receivers to determine the range to the transmitting GPS satellite A receiver that monitors four or more satellites simultaneously SiRF receivers can monitor 12 or more satellites simultaneously Position Dilution of Precision A measure of how much the error in the three dimensional position estimate produced from satellite range measurements is amplified by a poor satellite geometry with respect to the receiver antenna The mathematical constant having a value of approximately 3 14159 Peak to Peak Precise Positioning Service The GPS positioning velocity and time services that are available on a continuous worldwide basis to users authorized by the DoD C 3 Pseudorange PVT RAM Receiver Channels RF RFI ROM RTC RTCA RTCM SA Sa

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