gpsdev

Required Hardware

To run this example, you need:

Hardware Connection

Connect the pins on the UBlox Neo-6M GPS module to the pins on your USB to UART module. The connections are:

Connect the GPS antenna to the GPS module. Connect the USB to UART module to the host computer with a USB cable. GPS Fix can be easily acquired in locations that have a clear view of the sky. Wait for the GPS module to acquire satelite signals (Fix).This can be verified by checking the Fix LED (D1) of your GPS module.

Create GPS Object

Create a gpsdev object for the GPS module connected to a specific port.

gps = gpsdev('COM4')

gps = 
  gpsdev with properties:

                         SerialPort: COM4	
                           BaudRate: 9600 (bits/s)

                     SamplesPerRead: 1	 
                           ReadMode: "latest"	 
                        SamplesRead: 0	 
Show all properties all functions

Read the GPS data

Read the GPS data and extract latitude, longitude, and time from it. GPS returns UTC datetime. Convert it to system time zone.

[gpsData,~] = read(gps);
latitude = gpsData.LLA(1);
longitude = gpsData.LLA(2);
gpsTime = gpsData.GPSReceiverTime;
gpsTime.TimeZone = 'local';

Plot the position in a map along with the timestamp

Plot the position in geographic axes with the data obtained from the GPS module. GPS should have fix to get valid values for latitude, longitude and gpsTime.

If the GPS module does not have fix, the above commands give NaNs for latitude and longitude and NaT for gpsTime. In this case, make sure the antenna is exposed to clear sky and wait for some time and try the above steps again.

if(~isnan(latitude) && ~isnan(longitude))
 % plot the position in geographic coordinates
 fig = geoplot(latitude,longitude,'Marker',"o",'MarkerSize',6,'Color','red','MarkerFaceColor','red');

 % Sets the latitude and longitude limits of the base Map   
 geolimits([latitude-0.05 latitude+0.05],[longitude-0.05 longitude+0.05]) ;

 % Selects the basemap   
 geobasemap streets;
 timeString = strcat("Timestamp: ",string(gpsTime));

 % Create annotation and display time received from GPS
 annotation('textbox',[0.005 0.98 0.6 0.01],'FitBoxToText','on','string',timeString,'Color','blue','FontSize',10);
end

Clean Up

When the connection is no longer needed, clear the associated object.

delete(gps);
clear gps;

Required Hardware

To run this example, you need:

Hardware Connection

Connect the pins on the UBlox Neo-6M GPS module to the pins on your USB to UART module. The connections are:

Connect the GPS antenna to the GPS module. Connect the USB to UART module to the host computer with a USB cable. GPS Fix can be easily acquired in locations that have a clear view of the sky. Wait for the GPS module to acquire satelite signals (Fix).This can be verified by checking the Fix LED (D1) of your GPS module.

Create GPS Object

Connect to the GPS receiver using serialport object. Specify the port name and the baud rate.

s = serialport('COM4',9600)

s = 
  Serialport with properties:

                 Port: "COM4"
             BaudRate: 9600
    NumBytesAvailable: 0

  Show all properties, functions

gps = gpsdev(s)

gps = 
  gpsdev with properties:

                         SerialPort: COM4	
                           BaudRate: 9600 (bits/s)

                     SamplesPerRead: 1	 
                           ReadMode: "latest"	 
                        SamplesRead: 0	 
Show all properties all functions

Write Configuration Commands

In the default configuration the GPS receiver returns the following NMEA messages: GPRMC, GPVTG, GPGGA, GPGSA, GPGSV, and GPGLL. The receiver can be configured to have a user defined set of output messages.

Read few lines of default messages from the serial port the GPS receiver is connected.

for i = 1:10    
data = readline(s);
disp(data);
end

$GPRMC,,V,,,,,,,,,,N*53
$GPVTG,,,,,,,,,N*30
$GPGGA,,,,,,0,00,99.99,,,,,,*48
$GPGSA,A,1,,,,,,,,,,,,,99.99,99.99,99.99*30
$GPGSV,2,1,08,01,,,18,08,,,12,09,,,12,15,,,19*77
$GPGSV,2,2,08,23,,,13,24,,,09,25,,,10,27,,,25*79
$GPGLL,,,,,,V,N*64
$GPRMC,,V,,,,,,,,,,N*53
$GPVTG,,,,,,,,,N*30
$GPGGA,,,,,,0,00,99.99,,,,,,*48

Write the version monitor command to the GPS receiver to return the software and hardware version of the GPS receiver.

configCMD = [0xB5 0x62 0x0A 0x04 0x00 0x00 0x0E 0x34];
% writeBytes(gps,cfg)
write(s,configCMD,'uint8')

Read few lines of messages again to verify the version message.

for i = 1:10    
data = readline(s);
disp(data);
end

$GPGSA,A,1,,,,,,,,,,,,,99.99,99.99,99.99*30
$GPGSV,2,1,05,01,,,13,09,,,11,15,,,16,23,,,12*74
$GPGSV,2,2,05,25,,,10*7A
$GPGLL,,,,,,V,N*64
µb
( 7.03 (45969)                  00040007  °$GPRMC,,V,,,,,,,,,,N*53
$GPVTG,,,,,,,,,N*30
$GPGGA,,,,,,0,00,99.99,,,,,,*48
$GPGSA,A,1,,,,,,,,,,,,,99.99,99.99,99.99*30
$GPGSV,2,1,06,01,,,11,09,,,11,23,,,14,24,,,21*75

It can be observed from the output, 7.03 (45969) is the software version and 00040007 is the hardware version.

Clean Up

When the connection is no longer needed, clear the associated object.

delete(gps);
clear gps;
clear s;

Required Hardware

To run this example, you need:

Hardware Connection

Connect the pins on the UBlox Neo-6M GPS module to the pins on your USB to UART module. The connections are:

Connect the GPS antenna to the GPS module. Connect the USB to UART module to the host computer with a USB cable. GPS Fix can be easily acquired in locations that have a clear view of the sky. Wait for the GPS module to acquire satelite signals (Fix).This can be verified by checking the Fix LED (D1) of your GPS module.

Create GPS Object

Create a gpsdev object for the GPS receiver connected to a specific port. Specify the output format of the data as a timetable.

gps = gpsdev('COM4','OutputFormat',"timetable")

gps = 
  gpsdev with properties:

                         SerialPort: COM4	
                           BaudRate: 9600 (bits/s)

                     SamplesPerRead: 1	 
                           ReadMode: "latest"	 
                        SamplesRead: 0	 
Show all properties all functions

Read the GPS data

Read the GPS data and return them as a timetable.

[tt,overruns] = read(gps)

tt=1×5 timetable
              Time                         LLA               GroundSpeed    Course            DOPs                GPSReceiverTime     
    ________________________    _________________________    ___________    ______    ____________________    ________________________

    22-Mar-2021 15:31:15.190    17.47    78.343     449.6      0.25619       NaN      9.31    1.48    9.19    22-Mar-2021 10:01:14.000

overruns = 0

Display number of samples read and the samples available in the host buffer.

gps.SamplesRead

ans = 1

gps.SamplesAvailable

ans = 0

Release the GPS object to configure the non tunable properties. The release function also clears the buffer and resets the SamplesRead and SamplesAvailable properties.

release(gps)

Specify the number of samples per read to 2. Read the GPS data.

gps.SamplesPerRead = 2;
read(gps)

ans=2×5 timetable
              Time                         LLA               GroundSpeed    Course            DOPs                GPSReceiverTime     
    ________________________    _________________________    ___________    ______    ____________________    ________________________

    22-Mar-2021 15:31:17.178    17.47    78.343       450     0.063791       NaN      9.32    1.48     9.2    22-Mar-2021 10:01:16.000
    22-Mar-2021 15:31:17.178    17.47    78.343       450     0.063791       NaN      9.32    1.48     9.2    22-Mar-2021 10:01:16.000

Display number of samples read and the samples available in the host buffer.

gps.SamplesRead

ans = 1

gps.SamplesAvailable

ans = 0

Clean Up

When the connection is no longer needed, clear the associated object.

delete(gps);
clear gps;