sgm 108 manual en v1.0

SGM-108 GPS RECEIVER

ProGin Technology Inc.

N12F-1, No.5, Lane 7, De-an St., Lingya District,

Kaohsiung 802, Taiwan

Tel: 886-7-7278885 Fax: 886-7-7214117

E-mail: [email protected]

www.progin.com.tw

USER’S GUIDE

SGM-108 GPS Receiver USER’S GUIDE

SGM-108 User’s Guide v1.0

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Contents

1. Introduction ………………………………………………..…………. 2

1.1 Overview …………………………………………………………… …2

1.2 Features ……………………………………………………………..… 2

1.3 Electrical Characteristics ……………………………………………. 2

2. Hardware Interface …………………………………………………… 4

2.1 Dimension ……………………………………………………………. 4

2.2 Interface ……………………………………………………..……… 4

2.3 Connector ……………………………………………………...…..… 6

3. Operation ……………………………………………………………… 9

3.1 USB Driver Installation and Com Port Searching …………………… 9

3.2 Getting Start ………………………………………………………. 12

3.3 NctLite Viewer for Testing ………..………………………………… 13

3.4 Function …………………………………………………………… 14

3.5 Navigation ………………………………………………………….. 14

4. Warranty ………………………………………………….………… 14

Appendix: Software Specification ………………………………….. 15



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1. Introduction

1.1 Overview

The SGM-108 series GPS receiver incorporates low noise, high sensitivity, low power

consumption NemeriX chipset solution in a compact, waterproof enclosure. The receiver is

very suitable for broad applications such as car navigation, mapping, surveying, … etc.

Only clear view of sky and certain power supply are necessary to the unit. It communicates

with other host device via one full duplex serial communication RS-232 port or one universal

USB port. With its ultra low power consumption, the receiver tracks up to 16 satellites at a

time while offering fast time-to-first-fix, re-acquires satellite signals in 1 second (average)

and updates position data every second.

1.2 Features

The SGM-108 series provides a host of features that make it easy for integration and use.

1. Ultra low power design.

2. High performance receiver tracks up to 16 satellites.

3. Compact design ideal for applications with minimal space.

4. A rechargeable battery sustains internal clock and memory.

5. User initialization is not required.

6. One full duplex serial RS-232 port or USB port meets all applications.

7. Waterproof design for all weather.

8. Built-in low noise, high gain active antenna.

9. LED display provides users visible positioning status.

10. Support Standard NMEA-0183 at baud rate 4800

1.3 Electrical Characteristics General

Frequency L1, 1575.42 MHz C/A code 1.023 MHz chip rate Channels 16 channels all in view tracking Antenna internal

Sensitivity

Tracking -152 dBm typical Acquisition -147 dBm typical

Accuracy

Position 6.4 meters CEP (90 %) horizontal without SA



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Velocity 0.1 meters/second Time 1 microsecond synchronized to GPS time Datum Default WGS-84 Other Support different datum by request

Acquisition Rate

Hot start 12 sec, average Warm start 38 sec, average Cold start 50 sec, average

Dynamic Conditions

Altitude 10,000 meters max Horizontal Velocity 300 kilometers/hour max Vertical Velocity 36 kilometers/hour max Acceleration 2g max

Power

Main power input 3.3 ±5% VDC input. Supply Current 30 mA @ 3.3V

Serial Port

Electrical interface one full duplex serial communication, via RS232/ TTL interface, or universal USB interface

Protocol message NMEA-0183 Default NMEA GGA, GSA, GSV, RMC, 4800 baud rate, (VTG, GLL, and

RMS optional) 8 bits data, 1 start, 1 stop, no parity.

Time-1PPS Pulse (optional) Environmental Characteristics

Operating temperature range -40 oC to +80 oC Storage temperature range -45 oC to +95 oC



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2. Hardware Interface

2.1 Dimension

The receiver enclosure is with the dimension: 58.5 mm (L) x 52.5 mm (W) x 26.2 mm (H)

2.2 Interface

The SGM-108 series GPS receiver includes a variety of models. The main difference is the

output connector. These interface options are described in the following.

SGM-108

SGM-108 is with a PS2 DIN jack output connector. Following figure shows various

connection arrangements. The one-piece cigarette lighter adapter assembly allows you to

utilize power from the front power socket of vehicles. Simply connect SGM-108 to the

PS-2 plug of the adapter assembly and link the other connector to your PDA. For Notebook

users, a PS-2 to USB adapter assembly is required. This is an optional purchase. A CD

with USB driver is provided with the assembly. For users intend to use RS-232 port of PC

or Notebook, the other optional adaptor assembly can be purchased.



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SGM-108 USB

This model provides users a direct connection to a Notebook or other host devices with USB

connectors. USB driver is required and provided in the CD.

SGM-108 SN4

This model provides users a direct connection to SN4 connector. It is convenient for users

with SN4 connector in their host devices.

2.3 Connector

Following are the description of the output connector.

SGM-108

Standard cable is two meters in length with a female PS-2 Jack as shown in the following.

Pin assignment of standard PS-2 Din Jack connector is in the following drawing and table.

Pin Signal

1 Tx (RS-232)

2 +5VDC

3 Tx (TTL)

4 GND

5 Rx (TTL)

6 Rx (RS-232)



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The accessory is a Y-cable with a cigarette lighter adapter to a vehicle’s front power socket.

Please refer to the drawing on previous page. The Y cable is with one branch of PS2 Plug to

connect to the PS2 Jack of SGM-108, while the other branch to connect to a PDA. However,

due to the many variety of PDAs, an appropriate adaptor type must be specified.

For users with PC or Notebook, a USB interface cable or RS-232 adaptor cable shown in

previous page may be used. Drivers for the USB interface cable are available on a CD

associated with the cable. These are optional purchases.

SGM-108 USB

SGM-108 USB provides PC or Notebook users a convenient choice. There is no unusual

assignment about the connector. Definitions of USB connector pins are compliant with the

standard.



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SGM-108 SN4

SN4 connector is for users with specific requirements. Following is the outline.

Pin assignments of SN4 connector are in the following table.

Pin Signal

1 GND

2 Rx (RS232)

3 Tx (RS232)

4 +5VDC



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3. Operation

3.1 USB Driver Installation and Com Port Searching

For SGM-108 series GPS receiver using the USB type terminal, you have to install the driver

first. Here we use WinXP OS as an example. Please insert the installation CD into

CD-ROM drive. You can browse the CD contents and find the “USB Driver” folder.

Please open the folder and double click the PL-2303 driver icon. The installation will start.

Please click the “Next” button on the InstallShield Wizard’s “Welcome” window.



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Once the InstallShield Wizard completes the installation of the driver to your system, please

click “Finish” button.

You can plug the receiver’s USB terminal into USB port on your PC or NB now. However,

for receiving the GPS data stream properly, you have to set the correct Com port and Baud

rate in the utility software. Here is an easy approach for finding which Com port the mouse

is connecting to. Please click Start → Settings, and then select “Control Panel.”



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Please click the “System” icon and open the “System Properties” window.

Click the “Hardware” tab and find the “Device Manager” button on the page.



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Click the button and the window will show the hardware status. Please find the “Ports

(Com & LPT)” category and look for the Com port shown “Prolific USB-to-Serial Com

Port (COMxx)”, the xx is the Com port number you are connecting to.



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Although the above installation steps are under WinXP, basically the procedures are

somewhat the same for other Windows operating systems.

3.2 Getting Start

Connect the SGM-108 GPS receiver with an appropriate adaptor assembly. It depends on

the type of power source and host device. Install USB driver first when you connect to a

host device with a USB adaptor cable.

Take the GPS receiver to places with clear view of the sky. The Red LED indicates the

status.

(a) LED steady on when power is connected and for the initial acquisition process;

(b) LED flashes at 1 second period when the receiver outputs position fix data.



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3.3 NctLite Viewer for Testing

Install the NctLite viewer program to host device. You may check the status of the GPS receiver whenever you like to.

(a) Execute the NctLite program. Press the “COM” button to set “Com Port” for this data

link and “Baud Rate” to 4800.

(b) Click “OPEN” to download the received data. The lower right window shows the

NMEA format data stream and left window shows tracked satellite constellation and

signal quality status.

(c) Once the link is successful, click “CLOSE” button to exit the program. However, you

may click the “Cold” button to perform “cold start” testing.



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3.4 Function

As soon as the power on, the SGM-108 series GPS receiver begins the process of satellite

acquisition, and tracking. Under normal circumstances, it takes around 50 seconds (average)

to achieve a position fix at the first time, 38 seconds (average) if ephemeris data is known.

After a position fix has been calculated, information about valid position, velocity, and time

is transmitted over the output channel. The SGM-108 GPS receiver utilizes initial data,

such as last stored position, date, time and satellite orbital data, to achieve maximum

acquisition performance. If significant inaccuracy exists in the initial data or the orbital data

is obsolete, it may take more time to achieve a navigation solution.

3.5 Navigation

After the acquisition process is complete, the SGM-108 sends valid navigation information

over output channels. These data include:

1) Latitude/longitude/altitude

2) Velocity

3) Date/time

4) Error estimates

5) Satellite and receiver status

4. Warranty

The GPS smart receiver 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.



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Appendix: Software Specification

NMEA Protocol

The SGM-108 interface protocol is based on the National Marine Electronics Association

(NMEA) interface specification, namely, the NMEA 0183 standard. The SGM-108 is

capable of supporting the following NMEA message formats.

NMEA Message Prefix Format Direction

$GPGGA (1)* GPS fix data. Out

$GPGLL Geographic position Latitude / Longitude. Out

$GPGSA (1)* GNSS DOP and actives satellites Out

$GPGSV (3)* GNSS satellites in view. Out

$GPRMC (1)* Recommended minimum specific GNSS data. Out

$GPVTG Velocity and track over ground. Out

$GPZDA Date and time. Out

*: (1): 1 sec output 1 msg , (3): 3 sec output 1 msg ,

However, the default communication parameters for NMEA output are 4800 baud rate, 8 data

bits, 1 stop bit, and no parity, additionally, WGS84 datum (other datum are optional) and

GGA, GSA, GSV, and RMC format (GLL, VTG, and ZDA are optional upon request).

General NMEA Format

The general NMEA format consists of an ASCII string commencing with a ‘$’ character and

terminating with a <CR><LF> sequence. NMEA standard messages commence with ‘GP’

then a 3-letter message identifier. The message header is followed by a comma delimited

list of fields optionally terminated with a checksum consisting of an asterix ‘*’ and a 2 digit

hex value representing the checksum. There is no comma preceding the checksum field.

When present, the checksum is calculated as a bitwise exclusive of the characters between the

‘$’ and ‘*’. As an ASCII representation, the number of digits in each number will vary

depending on the number and precision, hence the record length will vary. Certain fields

may be omitted if they are not used, in which case the field position is reserved using

commas to ensure correct interpretation of subsequent fields.

The tables below indicate the maximum and minimum widths of the fields to allow for buffer

size allocation.



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$GPGGA

This message transfers global positioning system fix data. The $GPGGA message structure is shown below:

Field Format Min chars Max chars Notes

Message ID $GPGGA 6 6 GGA protocol header.

UTC Time hhmmss.sss 2,2,2.3 2,2,2.3 Fix time to 1ms accuracy.

Latitude float 3,2.4 3,2.4 Degrees * 100 + minutes.

N/S Indicator char 1 1 N=north or S=south

Longitude float 3,2.4 3,2.4 Degree * 100 + minutes.

E/W indicator Char 1 1 E=east or W=west

Position Fix Indictor Int 1 1 0: Fix not available or invalid. 1: GPS SPS mode. Fix available.

Satellites Used Int 2 2 Number of satellites used to calculate fix.

HDOP Float 1.1 3.1 Horizontal Dilution of Precision.

MSL Altitude Float 1.1 5.1 Altitude above mean seal level

Units Char 1 1 M Stands for “meters”.

Geoid Separation Int (0) 1 4 Separation from Geoids can be blank.

Units Char 1 1 M Stands for “meters”.

Age of Differential Corrections

int (0) 1 5 Age in seconds Blank (Null) fields when DGPS is not used.

Diff Reference Corrections

int 4 4 0000.

Checksum *xx (0) 3 3 2 digits.

Message terminator <CR> <LF> 2 2 ASCII 13, ASCII 10.

$GPGLL

This message transfers Geographic position, Latitude, Longitude, and time. The $GPGLL message structure is shown below:


Message ID $GPGLL 6 6 GLL protocol header.

Latitude Float 1,2.1 3,2.4 Degree * 100 + minutes.

N/S Indicator Char 1 1 N=north or S=south.

Longitude Float 1,2.1 3,2.4 Degree * 100 + minutes.

E/W indicator Character 1 1 E=east or W=west.


Status Char 1 1 A Data Valid. V Data invalid.

Mode Indicator Char 1 1 A Autonomous


Message terminator <CR><LF> 2 2 ASCII 13, ASCII 10.



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$GPGSA

This message transfers DOP and active satellites information. The $GPGSA message

structure is shown below:


Message ID $GPGSA 6 6 GSA protocol header.

Mode Char 1 1 M Manual, forced to operate in selected

mode. A Automatic switching between modes.

Mode Int 1 1 1 Fix not available. 2 2D position fix. 3 3D position fix.

Satellites Used Int 2 2 SV on channel 1.


… . .. .. ..


PDOP Float 1.1 3.1

HDOP Float 1.1 3.1

VDOP Float 1.1 3.1

Checksum *xx 0 3 2 digits

Message terminator <CR> <LF> 2 2 ASCII 13, ASCII 10



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$GPGSV

This message transfers information about satellites in view. The $GPGSV message

structure is shown below. Each record contains the information for up to 4 channels,

allowing up to 12 satellites in view. In the final record of the sequence the unused

channel fields are left blank with commas to indicate that a field has been omitted.

Field Format Min

chars Max chars Notes

Message ID $GPGSV 6 6 GSA protocol header.

Number of messages

Int 1 1 Number of messages in the message sequence from 1 to 3.

Message number Int 1 1 Sequence number of this message in current sequence, from 1 to 3.

Satellites in view Int 1 2 Number of satellites currently in view.

Satellite Id Int 2 2 Satellite vehicle 1.

Elevation Int 1 3 Elevation of satellite in degrees.

Azimuth Int 1 3 Azimuth of satellite in degrees.

SNR Int (0) 1 2 Signal to noise ration in dBHz, null if the sv is not in tracking.

















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$GPRMC This message transfers recommended minimum specific GNSS data. The $GPRMC message format is shown below.

Field Format Min chars Max

chars Notes

Message ID $GPRMC 6 6 RMC protocol header.


Status char 1 1 A Data Valid. V Data invalid.

Latitude Float 1,2.1 3,2.4 Degrees * 100 + minutes.

N/S Indicator Char 1 1 N=north or S=south.

Longitude Float 1,2.1 3,2.4 Degrees * 100 + minutes.

E/W indicator Char 1 1 E=east or W=west.

Speed over ground Float 1,1 5.3 Speed over ground in knots.

Course over ground Float 1.1 3.2 Course over ground in degrees.

Date ddmmyy 2,2,2 2,2,2 Current date.

Magnetic variation Blank (0) (0) Not used.

E/W indicator Blank (0) (0) Not used.

Mode Char 1 1 A Autonomous



$GPVTG This message transfers Velocity, course over ground, and ground speed. The $GPVTG message format is shown below.


Message ID $GPVTG 6 6 VTG protocol header.

Course (true) Float 1.1 3.2 Measured heading in degrees.

Reference Char 1 1 T = true heading.

Course (magnetic) Float 1.1 3.2 Measured heading (blank).

Reference Char 1 1 M = magnetic heading.

Speed Float 1.1 4.2 Speed in knots.

Units Char 1 1 N = knots.

Speed Float 1.1 4.2 Speed

units Char 1 1 K = Km/h.

Mode Char 1 1 A Autonomous





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$GPZDA

This message transfers UTC Time and Date. Since the latency of preparing and

transferring the message is variable, and the time does not refer to a particular position

fix, the second precision is reduced to 2 decimal places. The $GPZDA message format

is shown below.


Message ID $GPZDA 6 6 ZDA protocol header.

UTC time hhmmss.ss 2,2,2.2 2,2,2.2 00000000.00 to 235959.99

UTC day dd 2 2 01 to 31, day of month.

UTC month mm 2 2 01 to 12.

UTC Year yyyy 4 4 1989-9999.

Local zone hours Int (-)2 (-)2 Offset of local time zone (-13) to 13.

Local zone minutes Unsigned 2 2



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