ET-316A GPS Engine Board ET-316A Version 1.2 06/22/2007 Globalsat Technology Corporation Headquarters (Far East Century Park) 16F., No. 186, Jian-Yi Road, Chung-Ho City, Taipei Hsien 235, Taiwan Tel: 886-2-8226-3799/ Fax: 886-2-8226-3899 E-mail : service@globalsat.com.tw Website: www.globalsat.com.tw Page 1 of 17 Version 1.
ET-316A Version 1.2 1. Product Information Product Name: ET-316A Product Description: ET-316A is a compact, high performance, and low power consumption GPS engine board. It uses SiRF Star III chipset which can track up to 20 satellites at a time and perform fast TTFF in weak signal environments.
ET-316A Version 1.2 Channels 20 Flash 4Mbit Sensitivity Tracking:-159dBm Cold Start 42 seconds, average Warm Start 38 seconds, average Hot Start 1 second, average Reacquisition 0.1 second, average Accuracy Position: 10 meters, 2D RMS 5 meters, 2D RMS, WAAS enabled Velocity: 0.
ET-316A Version 1.2 2. Technical Information Block Diagram Module Pin Assignment: Pin NO. Pin Name Remark 1. GND Ground. 2. RF Connect to External Active Antenna. While external antenna is used, the optional power is needed. 3. GND Ground. 4. GND Ground. 5. GND Ground. The Specifications are subject to be changed without notice. Page 4 of 17 Copyright © 2007, GlobalSat Technology.
ET-316A 6. Version 1.2 GND Ground. 7. VIN This is the main DC supply for a 3.3V +- 5% DC input power module board. 8. BATTERY This is the battery backup input that powers the SRAM and RTC when main power is removed. Typical current draw is 15uA. Without an external backup battery, the module/engine board will execute a cold star after every turn on. To achieve the faster start-up offered by a hot or warm start, a battery backup must be connected. The battery voltage should be between 2.0v and 5.0v.
ET-316A Version 1.2 Application Circuit GPS Active Antenna Specification(Recommendation) Frequency: 1575.42+2 MHz Axial Ratio: 3 dB Typical output Impedance: 50Ω Polarization: RHCP Amplifier Gain :18~22dB Typical Output VSWR: 2.0 Max. Noise Figure: 2.0 dB Max The Specifications are subject to be changed without notice. Page 6 of 17 Copyright © 2007, GlobalSat Technology.
ET-316A Version 1.2 Dimensions The Specifications are subject to be changed without notice. Page 7 of 17 Copyright © 2007, GlobalSat Technology.
ET-316A Version 1.2 Recommend Layout PAD The Specifications are subject to be changed without notice. Page 8 of 17 Copyright © 2007, GlobalSat Technology.
ET-316A Version 1.2 SOFTWARE COMMAND NMEA Output Command GGA-Global Positioning System Fixed Data Table B-2 contains the values for the following example: $GPGGA,161229.487,3723.2475,N,12158.3416,W,1,07,1.0,9.0,M,,,,0000*18 Table B-2 GGA Data Format Name Example Message ID UTC Time Latitude N/S Indicator Longitude E/W Indicator Position Fix Indicator Satellites Used HDOP MSL Altitude1 Units Geoid Separation1 Units Age of Diff. Corr. Diff. Ref. Station ID Checksum $GPGGA 161229.487 3723.
ET-316A Version 1.2 Table B-4 GLL Data Format Name Message ID Latitude N/S Indicator Longitude E/W Indicator UTC Position Status Checksum Example $GPGLL 3723.2475 n 12158.3416 W 161229.487 A *2C Units Description GLL protocol header ddmm.mmmm N=north or S=south dddmm.mmmm E=east or W=west hhmmss.sss A=data valid or V=data not valid End of message termination GSA-GNSS DOP and Active Satellites Table B-5 contains the values for the following example: $GPGSA,A,3,07,02,26,27,09,04,15,,,,,,1.8,1.
ET-316A Version 1.2 $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 Table B-8 GSV Data Format Name Message ID Number of Messages1 Message Number1 Satellites in View Satellite ID Elevation Azimuth SNR(C/No) …….
ET-316A Version 1.2 VTG-Course Over Ground and Ground Speed $GPVTG,309.62,T,,M,0.13,N,0.2,K*6E Name Example Message ID Course Reference Course Reference Speed Units Speed Units Checksum 2.2 $GPVTG 309.62 T Units degrees degrees M 0.13 N 0.2 K *6E knots Km/hr Description VTG protocol header Measured heading True Measured heading Magnetic Measured horizontal speed Knots Measured horizontal speed Kilometers per hour End of message termination NMEA Input Command A).
ET-316A Version 1.2 0=None, 1=Odd, 2=Even Example 1: Switch to SiRF Binary protocol at 9600,8,N,1 $PSRF100,0,9600,8,1,0*0C Example 2: Switch to User1 protocol at 38400,8,N,1 $PSRF100,4,38400,8,1,0*38 **Checksum Field: The absolute value calculated by exclusive-OR the 8 data bits of each character in the Sentence,between, but excluding “$” and “*”.
ET-316A Version 1.2 value if available. If this is unavailable, a default value of 75000 for GSP1, 95000 for GSP 1/LX will be used. INT32 GPS Time Of Week UINT32 GPS Week Number UINT16 （ Week No and Time Of Week calculation from UTC time） Number of channels to use.1-12.
ET-316A Version 1.2 0=None,Odd=1,Even=2 Example: Set DGPS Port to be 9600,8,N,1 ＄PSRF102,9600,8,1.0*12 D). Query/Rate Control ID:103 Query standard NMEA message and/or set output rate This command is used to control the output of standard NMEA message GGA, GLL, GSA, GSV RMC, VTG. Using this command message, standard NMEA message may be polled once, or setup for periodic output. Checksums may also be enabled or disabled depending on the needs of the receiving program.
ET-316A Version 1.2 , *CKSUM Latitude position, assumed positive north of equator and negative south of equator float, possibly signed Longitude position, it is assumed positive east of Greenwich and negative west of Greenwich Float, possibly signed Altitude position float, possibly signed Clock Offset of the receiver in Hz, use 0 for last saved value if available.
ET-316A Version 1.2 GPS receivers perform initial position and velocity calculations using an earth-centered earth-fixed (ECEF) coordinate system. Results may be converted to an earth model (geoid) defined by the selected datum. The default datum is WGS 84 (World Geodetic System 1984) which provides a worldwide common grid system that may be translated into local coordinate systems or map datums. (Local map datums are a best fit to the local shape of the earth and not valid worldwide.
