GPS Emulator

 

Introduction:

The GPS Emulator application emulates the functions of a GPS Receiver. The latest version of the application was developed with Visual Studio 2005 and compiled with the .NET Framework Version 2.0.50727. The GPS Emulator transmits NMEA sentences on either serial port COM1 or COM2 or a Virtual Serial Port or all three (if required). A virtual serial port driver is attached, courtesy of Vyacheslav Frolov.

 

Mapping:

The real time mapping is courtesy of Microsoft, i.e. the Microsoft MapPoint staging server.

 

Feature Request:

If this application is not what you expected send me an email and I will accommodate your feature request. ( tgarai at optusnet dot com dot au ).

 

NMEA:

 

The starting point for the application is the nmea.txt file. The nmea.txt file is a text file containing the NMEA sentences to send to the serial ports. Each NMEA sentence should be correctly formatted as per the NMEA (National Marine Electronics Association) standard (0183).

 

Nmea.txt files are bundled together with the GPS Emulator, however any textual GPS receiver output can be captured to a text file and re-used by this emulator.

 

Figure 1: GPS Emulator

 

 

Features:

·        Selectable transmission of NMEA sentences:

o       RME, RMZ, RMM, RTE, GSA, RMB, GSV, GLL, GGA, RMC, ZDA.

·        Real Time Test Option Generator

o       Generate incorrect checksum

o       Generate random GPS coordinates

·        NMEA Data Generation:

o       Generate NMEA dates

o       Set speed

o       Time Offset, Hours and Minutes

·        Configuration options:

o       Specify Serial Port parameters:

§         Baud, parity, stop bits, data bits, Flow control

·        Map display

o       Displays the map centred on the GPS coordinates anywhere in the world

§         Specify Map Width and Height

·        Speed and course indication

·        Display of NMEA sentences transmitted

·        Serial Port Selection

o       COM1, COM2 or both

 

Pre-requisites:

• Windows 2000 or Windows XP
• .NET runtime V2.0.50727
• Internet Connection
• Null modem serial cable DB9 or DB25

 

Installation:

• Read and agree with the Licence agreement.
• Download the GPS Emulator

• Download and Install the .NET runtime V2.0.50727
• Download and unzip the GPS Emulator application into a selected directory

 

Quick Start:

• Connect the serial port of the computer (COM1 or COM2) to the device reading GPS using the null modem serial cable.
• Start the application.
• Click the Start button.

 

GPS Emulator Operation:

 

NMEA Sentences:

-         Select the NMEA sentence combinations to emit to the serial port. By default GLL GGA and RMC are selected.

Test Options:

-         Toggle the Bogus Checksum checkbox during run time to generate incorrect NMEA sentence checksums. This should generate device read errors on the device reading the GPS data.

-         Toggle the Bogus Coords checkbox during runtime to generate random GPS coordinates. The device reading the GPS data should generate errors and/or handle erroneous data correctly

-         Age selection: select the days to subtract from the current date. This new date value is the date string that shall be used in the NMEA sentences

-         Speed selection: select the desired speed to be used in the NMEA sentences. Note: if the speed is greater than zero the NMEA sentences will used this value for the speed (in knots) otherwise the values specified in the nmea.txt file will be used by default.

Configuration Options:

-         GPS interval: select the value in milliseconds to be used for the time interval that the GPS data is sent to the serial port (per NMEA sentence).

-         Serial Ports: Select the serial port(s) to use for GPS data output, COM1 or COM2 or both

Time Zone Correction:

-         Select the time in hours and minutes to be added to the current time UTC to be used with the NMEA sentences data sent to the serial port(s).

GPS File:

-         Select the nmea.txt file to use in the emulation.

Map width:

-         Sets the map width in kilometres across to display.

Map height:

-         Sets the map height in kilometres above the earth to display.

 

Direction of Travel:

-         The direction of travel is displayed in the compass image

Speed:

-         The speed of travel in knots ( 1 Knot = 1.825 kilometres per hour) is displayed in the Speedo image.

Transmitted:

-         The NMEA sentences transmitted is displayed in this list box in purple text.

 

Map:

-         The map of the earth centred on the GPS coordinates provided by the NMEA sentences read in is displayed in the map control. For the map to render there must be an active internet connection.