GR-271 CF GPS Receiver User’s Guide Aug 17, 2006
TABLE OF CONTENTS 1. Introduction ……………………………………………………………………………………….. 1.1 Overview …………………………………………………………………………………….. 1.2 Features …………………………………………………………………………………….. 3 3 3 2. Brief Information ……………………………………………………………….………………… 2.1 Hardware Interface …………………………………………………………………………… 2.2 Software Interface …………………………………………………………………………… 5 5 6 3. Functional Test ………………………………………………………………………….…… 9 4. Trouble Shooting …………………………………………………………………………….… 12 5.
1. Introduction 1.1 Overview 1.2 Features The GR-271 provides a host of features that make it easy for integration and use. z 20 parallel satellite-tracking channels for fast acquisition and reacquisition z Built-in hardware tracking loop processor WAAS/EGNOS demodulator z Low power consumption with starШ chipset z Built-in rechargeable battery for memory and RTC backup and for fast time to first fix(TTFF) z Support NMEA0183 v2.
2. Brief Information 2.1 Hardware Interface 2.1.1 GR-271 Dimension 93.5 (L) x 43 (W) x 11 (H) mm 2.1.
A. Link to PDA B.
2.1.3 LED & External Antenna ◆ LED LED OFF GR-271 CF GPS Receiver Switch Off. LED ON GR-271 CF GPS Receiver Signal Searching. LED Flashing GR-271 CF GPS Receiver Signal Position Fixed. ◆ External Antenna Connector (MCX)…..Optional As using GR-271 CF GPS Receiver in a RV car, truck or bus, it might receive poor signals through limited view to the sky. Replace the foldable antenna with the active one to get better satellite signals.
MSL Altitude Units Geoid Separation Units Age of Diff. Corr. Diff. Ref. Station ID Checksum Value 0 1 2 3 9.0 M Meters Meters Meters Meters second M Null fields when DGPS is not used 0000 *18 End of message termination Table 2-3 Position Fix Indicator Description 0 Fix not available or invalid GPS SPS Mode, fix valid Differential GPS, SPS Mode, fix valid GPS PPS Mode, fix valid 2.2.1.
$GPGSV,2,1,07,07,79,048,42,02,51,062,43,26,36,256,42,27,27,138,42*71 $GPGSV,2,2,07,09,23,313,42,04,19,159,41,15,12,041,42*41 Name Message ID Number of Messages Message Number Satellites in View Satellite ID Elevation Azimuth SNR (C/No) .... Satellite ID Elevation Azimuth SNR (C/No) Checksum Example $GPGSV 2 1 07 07 79 048 42 ....
communication parameters, GR-271 may decode the data correctly to generate accurate messages and save them in battery-back SRAM for later computing. 3. Functional Test ◆ Install Guide： 1. Install GPSViewer.exe from PC to your PDA(Microsoft Pocket PC OS or alike). (1) Install Microsoft ActiveSync to your PC, refer to your Pocket PC manual for installation procedure. (2) Setup your Pocket PC cradle to Desktop PC UART port. The Microsoft ActiveSync will detect your Pocket PC automatically.
2. Push “Start”→”programs” bottom→“ GPS Viewer” 3. Push “Scan” bottom to scan your Com Port. then push “Open GPS” bottom.
4. Select “GPS Status” to show the satellite diagram like below.
4. Trouble Shooting Problem Reason Weak or no GPS signal can be received at the place of GR-271 CF GPS No position output but timer is counting At outdoor space but GPS signal is blocked by buildings or car roof. Execute Fail Wrong CPU Type Can’t Open GR-271 CF GPS is not inserted or some other COM port application is using the COM port. Can’t Find GPS Poor connection Module No action for few minutes may cause Pocket PC entry power save mode. It will close the COM port at the same time.
5. Specifications z Tracks up to 20 satellites. z Receiver: L1, C/A code z Snap Start: <3 sec(at < 25 minutes off z power On/Off and Navigation Update Indication period). z Update rate: 1 HZ. z Acquisition time z z Operation Temperature: -10 Reacquisition 0.1sec.averaged Hot start 8 sec., averaged Warm start 38 sec., averaged Cold start 42 sec., averaged z z Position 5-25 m CEP without SA Velocity 0.
6. Warranty The GR-271 is warranted to be free from defects in material and functions for one year from the date of purchase. Any failure of this product within this period under normal conditions will be replaced at no charge to the customers.
