Global Sat ET-332 User manual

ET-332
Specifications are subject to be changed without notice.
Page 1 of 15
Version 1.3.1
GPS Engine Board
ET-332
Globalsat Technology Corporation
16F., No. 186, Jian-Yi Road, Chung-Ho City, Taipei Hsien 235,
Ta i wa n
Tel: [phone]/ Fax: [phone]
[e-mail]
www.globalsat.com.tw
USGlobalSat, Inc.
1308 John Reed Court, City of Industry, CA 91745
Tel: [phone] / Fax: [phone]
[e-mail]
www.usglobalsat.com

ET-332
Specifications are subject to be changed without notice.
Page 2 of 15
Version 1.3.1
1. Product Information
Product Part I.D. ET-332
Product Description:
The ET-332 GPS engine board is low cost but maintains high reliability and accuracy making it an
ideal choice for integration with OEM/ODM systems.
Product Features:
9SiRF Star III/ LP Single
9Very high sensitivity (Tracking Sensitivity: -159dBm)
9Compact PCB allows for easier integration into space limited environments.
9Supports the NMEA 0183 data protocol
9Foliage Lock for weak signal tracking
9All-in-view 20-channel parallel processing
9Snap Lock 100mc re-acquisition time
9Enhanced algorithm for navigation stability
9Superior urban canyon performance
9WAAS / EGNOS MSAS support
9Built-in SuperCap to maintain system data for rapid satellite acquisition
9RoHS compliant
Product Specifications
GPS Receiver
Chipset SiRF Star III/LP Single
Frequency L1, 1575.42 MHz
Code 1.023 Mhz chip rate
Protocol Electrical Level: TTL level,
Output Voltage Level: 0V~2.85V
Baud Rate: 4800 bps
Output Message: NMEA 0183 GGA, GSA,
GSV, RMC (VTG, GLL optional)
Channels 20
Sensitivity -159dBm
Cold Start 42 seconds average

ET-332
Specifications are subject to be changed without notice.
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Version 1.3.1
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: 0.1 m/s
Time: 1us synchronized to GPS time
Maximum Altitude 18,000 meter (60,000 feet) max
Maximum Velocity 515 meter/second (1000 knots) max
Maximum Acceleration 4G
Jerk 20m/sec **3
Interface
I/O Connector Type
External Antenna Port
Physical Characteristics
Dimensions 1.6” x 1.4” x 0.4” (40.5 x 35 x 10 mm)
DC Characteristics
Power Supply 3.8V ~ 6.5V DC Input
Backup Voltage 2.5 ~ 3.6V 10uA backup current
Power Consumption 42mA (Continuous Mode)
25mA (Trickle Power Mode)
Environmental Range
Humidity Range 5% to 95% non-condensing
Operation Temperature -40F to +176F (-40C to +85C)

ET-332
Specifications are subject to be changed without notice.
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Version 1.3.1
2. Technical Information
Physical Characteristics

ET-332
Specifications are subject to be changed without notice.
Page 5 of 15
Version 1.3.1
Pin Assignment
Pin Name Description Type
1 GND Ground
2 VBAT Backup Battery Input
3 VDC 3.8V~6.5V DC Power Input Input
4 PBRES Push Button Reset Input (Active Low) Input
5 GPIO1 (Reserved)
6 TXA Serial Data Output A (GPS Data) Output
7 RXA Serial Data Input A (Command) Input
8 GND Ground
9 GND Ground
10 SELECT (Reserved)
11 TIMEMARK 1PPS Time Mark Output Output
12 GND Ground

ET-332
Specifications are subject to be changed without notice.
Page 6 of 15
Version 1.3.1
Pin Explanation
VCC: (DC power input) This is the main DC supply for a 3.8V ~ 6.5V power module board.
VBAT: This is the battery backup input that powers the SRAM and RTC when main power is removed.
Typical current draw is 10uA. 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. To maximize battery lifetime, the battery voltage should be between 2.5v and
3.6v.
PBRES: (Push Button Reset) This pin provides an active-low reset input to the engine board. It causes
the engine board to reset and start searching for satellites.
SELECT: Do not connect (do not use)
TX: This is the main transmit channel for outputting navigation and measurement data to user’s
navigation software or user-written software. Output TTL level, 0V ~ 2.85V
RX: This is the main receive channel for receiving software commands to the engine board from
SiRfdemo software or from user-written software. (NOTE:When not in use this pin must be kept “HIGH”
for operation. From Vcc connect a 470 Ohm resistor in series with a 3.2v Zener diode to Ground. Then,
connect the Rx input to Zener’s cathode to pull the input “HIGH”.)
TIME MARK (1PPS): This pin provides one pulse-per-second output from the engine board that is
synchronized to GPS time
GND: GND provides the ground for the engine boards. Be sure to connect all grounds
Mounting
Recommended mounting methods:
a. Use industrial grade double-sided foam tape. Place it on the bottom side of the engine board.
b. A recessed cavity in your housing design with a foam pad to eliminate shifting or movement.
c. Use provided mounting holes on the GPS engine board PCB.
3. Software Commands
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

ET-332
Specifications are subject to be changed without notice.
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Version 1.3.1
Table B-2 GGA Data Format
Name Example Units Description
Message ID $GPGGA GGA protocol header
UTC Time 161229.487 hhmmss.sss
Latitude 3723.2475 ddmm.mmmm
N/S Indicator N N=north or S=south
Longitude 12158.3416 dddmm.mmmm
E/W Indicator W E=east or W=west
Position Fix Indicator 1 See Table B-3
Satellites Used 07 Range 0 to 12
HDOP 1.0 Horizontal Dilution of Precision
MSL Altitude19.0 meters
Units M meters
Geoid Separation1meters
Units M meters
Age of Diff. Corr. second Null fields when DGPS is not used
Diff. Ref. Station ID 0000
Checksum *18
<CR><LF> End of message termination
SiRF Technology Inc. does not support geoid corrections. Values are WGS84 ellipsoid heights.
Table B-3 Position Fix Indicator
Value Description
0 Fix not available or invalid
1 GPS SPS Mode, fix valid
2 Differential GPS, SPS Mode , fix valid
3 GPS PPS Mode, fix valid
GLL-Geographic Position-Latitude/Longitude
Table B-4 contains the values for the following example:
$GPGLL,3723.2475,N,12158.3416,W,161229.487,A*2C
Table B-4 GLL Data Format
Name Example Units Description
Message ID $GPGLL GLL protocol header
Latitude 3723.2475 ddmm.mmmm
N/S Indicator n N=north or S=south
Longitude 12158.3416 dddmm.mmmm
E/W Indicator W E=east or W=west

ET-332
Specifications are subject to be changed without notice.
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Version 1.3.1
UTC Position 161229.487 hhmmss.sss
Status A A=data valid or V=data not valid
Checksum *2C
<CR><LF> 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,,,,,,1.8,1.0,1.5*33
TableB-5GSADataFormat
Name Example Units Description
Message ID $GPGSA GSA protocol header
Mode1 A See Table B-6
Mode2 3 See Table B-7
Satellite Used107 Sv on Channel 1
Satellite Used102 Sv on Channel 2
.
Satellite Used1Sv on Channel 12
PDOP 1.8 Position dilution of Precision
HDOP 1.0 Horizontal dilution of Precision
VDOP 1.5 Vertical dilution of Precision
Checksum *33
<CR><LF> End of message termination
1. Satellite used in solution.
TableB-6Mode1
Value Description
M Manual-forced to operate in 2D or 3D mode
A 2D automatic-allowed to automatically switch 2D/3D
TableB-7Mode2
Value Description
1 Fix Not Available
2 2D
3 3D
GSV-GNSS Satellites in View
Table B-8 contains the values for the following example:
$GPGSV,2,1,07,07,79,048,42,02,51,062,43,26,36,256,42,27,27,138,42*71

ET-332
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Version 1.3.1
$GPGSV,2,2,07,09,23,313,42,04,19,159,41,15,12,041,42*41
TableB-8GSVDataFormat
Name Example Units Description
Message ID $GPGSV GSV protocol header
Number of Messages12 Range 1 to 3
Message Number11 Range 1 to 3
Satellites in View 07
Satellite ID 07 Channel 1(Range 1 to 32)
Elevation 79 degrees Channel 1(Maximum90)
Azimuth 048 degrees Channel 1(True, Range 0 to 3
5
SNR(C/No) 42 dBHz Range 0 to 99,null when not tr
a
……. …….
Satellite ID 27 Channel 4 (Range 1 to 32)
Elevation 27 Degrees Channel 4(Maximum90)
Azimuth 138 Degrees Channel 4(True, Range 0 to 3
5
SNR(C/No) 42 dBHz Range 0 to 99,null when not tr
a
Checksum *71
<CR><LF> End of message termination
Depending on the number of satellites tracked multiple messages of GSV data may be required.

ET-332
Specifications are subject to be changed without notice.
Page 10 of 15
Version 1.3.1
RMC-Recommended Minimum Specific GNSS Data
Table B-9 contains the values for the following example:
$GPRMC,161229.487,A,3723.2475,N,12158.3416,W,0.13,309.62,120598,,*10
Table B-9 RMC Data Format
Name Example Units Description
Message ID $GPRMC RMC protocol header
UTC Time 161229.487 hhmmss.sss
Status A A=data valid or V=data not valid
Latitude 3723.2475 ddmm.mmmm
N/S Indicator N N=north or S=south
Longitude 12158.3416 dddmm.mmmm
E/W Indicator W E=east or W=west
Speed Over Ground 0.13 knots
Course Over Ground 309.62 degrees True
Date 120598 ddmmyy
Magnetic Variation2degrees E=east or W=west
Checksum *10
<CR><LF> End of message termination
SiRF Technology Inc. does not support magnetic declination. All “course over ground” data are
Geodetic WGS48 directions.
VTG-Course Over Ground and Ground Speed
$GPVTG,309.62,T,,M,0.13,N,0.2,K*6E
Table B-9 VTG Data Format
Name Example Units Description
Message ID $GPVTG VTG protocol header
Course 309.62 degrees Measured heading
Reference T True
Course degrees Measured heading
Reference M Magnetic
Speed 0.13 knots Measured horizontal speed
Units N Knots
Speed 0.2 Km/hr Measured horizontal speed
Units K Kilometers per hour
Checksum *6E
<CR><LF> End of message termination