How to the Blox location from GNSS with the IB-0310
The LTE modem that is mounted in the mPCIE slot with the IB-0310 includes a GNSS module. The location of the Blox device can be retreived from this module. To retreive the location data the gpsd needs to be configured first. gpsd is a daemon that acts as an intermediary between GPS (Global Positioning System) receivers and user applications. Once configured the location data can be displayed in the terminal or retrieved form software.
gpsd config
Before the gpsd can be used, proper configuration of the interface to the GNSS/GPS module needs to be done.
The GNSS module which is included in the SIM7600E-H modem will use one of the exposed serial to USB connections. By default this is /dev/ttyUSB1 for GNSS data and has a baudrate of 115200.
Open the gpsd config file
sudo nano /etc/default/gpsd
Set the correct interface for the GNSS under DEVICES= and also add the BAUDRATE=”115200”
# Devices gpsd should collect to at boot time.
# They need to be read/writeable, either by user gpsd or the group dialout.
DEVICES="/dev/ttyUSB1"
BAUDRATE="115200"
The file should look like this after the changes.
# Default settings for the gpsd init script and the hotplug wrapper.
# Start the gpsd daemon automatically at boot time
START_DAEMON="true"
# Use USB hotplugging to add new USB devices automatically to the daemon
USBAUTO="true"
# Devices gpsd should collect to at boot time.
# They need to be read/writeable, either by user gpsd or the group dialout.
DEVICES="/dev/ttyUSB1"
BAUDRATE="115200"
# Other options you want to pass to gpsd
GPSD_OPTIONS=""
Now close and save the file.
Before the new settings are used, the gpsd needs to restart or the system should reboot.
sudo systemctl restart gpsd
Retreiving GPS data in the Terminal
To display gps data in the terminal you can use gpsmon or cgps .
gpsmon
gpsmon
GPS data output
tcp://localhost:2947 NMEA0183>
┌──────────────────────────────────────────────────────────────────────────────┐o
│Time: 2023-10-26T11:51:38.000Z Lat: 50 50' 48.03224" Non: 4 21' 32.04234" E│v
└───────────────────────────────── Cooked TPV ─────────────────────────────────┘"
┌──────────────────────────────────────────────────────────────────────────────┐f
│ GLGSV BDGSV GPGSV GPGGA PQXFI GNGNS GPVTG GPRMC GPGSA GNGSA BDGSA PQGSA │
└───────────────────────────────── Sentences ──────────────────────────────────┘
┌──────────────────┐┌────────────────────────────┐┌────────────────────────────┐
│Ch PRN Az El S/N ││Time: 115138.00 ││Time: 115138.00 │
│ 0 86 277 26 47 ││Latitude: 5050.805374 N ││Latitude: 5050.805374 │
│ 1 79 39 33 26 ││Longitude: 00421.540391 E ││Longitude: 00421.540391 │
│ 2 69 99 18 32 ││Speed: 0.0 ││Altitude: 90.3 │
│ 3 87 334 19 36 ││Course: ││Quality: 1 Sats: 06 │
│ 4 71 302 37 43 ││Status: A FAA: A ││HDOP: 0.9 │
│ 5 70 35 74 0 ││MagVar: 1.8 W ││Geoid: 47.0 │
│ 6 73 174 18 0 │└─────────── RMC ────────────┘└─────────── GGA ────────────┘
│ 7 80 119 56 0 │┌────────────────────────────┐┌────────────────────────────┐
│ 8 85 232 6 0 ││Mode: A2 ...s: 86 79 69 87 ││UTC: RMS: │
│ 9 5 300 43 47 ││DOP: H=0.9 V=0.8 P=1.3 ││MAJ: MIN: │
│10 7 78 63 27 ││TOFF: 0.022214302 ││ORI: LAT: │
│11 11 223 27 30 ││PPS: ││LON: ALT: │
└────── GSV ───────┘└──────── GSA + PPS ─────────┘└─────────── GST ────────────┘
(75) $GPGGA,115138.00,5050.805374,N,00421.540391,E,1,06,0.9,90.3,M,47.0,M,,*55
(69) $PQXFI,115138.0,5050.805374,N,00421.540391,E,90.3,7.57,4.24,0.10*5C
(75) $GNGNS,115138.00,5050.805374,N,00421.540391,E,AAN,12,0.9,90.3,47.0,,,V*50
(34) $GPVTG,,T,1.8,M,0.0,N,0.0,K,A*04
(72) $GPRMC,115138.00,A,5050.805374,N,00421.540391,E,0.0,,261023,1.8,W,A*0B
(51) $GPGSA,A,2,05,07,11,13,20,30,,,,,,,1.3,0.9,0.8*31
(53) $GNGSA,A,2,05,07,11,13,20,30,,,,,,,1.3,0.9,0.8,1*32
(53) $GNGSA,A,2,69,71,79,80,86,87,,,,,,,1.3,0.9,0.8,2*3E
(41) $GNGSA,A,2,,,,,,,,,,,,,1.3,0.9,0.8,3*31
(30) $BDGSA,A,1,,,,,,,,,,,,,,,*0F
cgps
cgps or client gps displays the full json message received from the GNSS module.
cgps
Output
┌───────────────────────────────────────────┐┌─────────────────────────────────┐
│ Time: 2023-10-26T11:57:51.000Z ││PRN: Elev: Azim: SNR: Used: │
│ Latitude: 50.84676489 N ││ 69 16 102 24 Y │
│ Longitude: 4.35901183 E ││ 71 40 305 45 Y │
│ Altitude: 295.932 ft ││ 73 21 174 29 Y │
│ Speed: 0.00 mph ││ 79 31 036 29 Y │
│ Heading: 0.0 deg (true) ││ 80 58 113 18 Y │
│ Climb: 0.00 ft/min ││ 86 24 274 43 Y │
│ Status: 3D FIX (6 secs) ││ 87 20 331 36 Y │
│ Longitude Err: +/- 30 ft ││ 70 73 047 00 N │
│ Latitude Err: +/- 34 ft ││ 85 03 230 20 N │
│ Altitude Err: +/- 52 ft ││ │
│ Course Err: n/a ││ │
│ Speed Err: +/- 47 mph ││ │
│ Time offset: 0.022 ││ │
│ Grid Square: JO20eu ││ │
└───────────────────────────────────────────┘└─────────────────────────────────┘
{"class":"VERSION","release":"3.17","rev":"3.17","proto_major":3,"proto_minor":12}
18Z","flags":1,"native":0,"bps":9600,"parity":"N","stopbits":1,"cycle":1.00}]}
{"class":"WATCH","enable":true,"json":true,"nmea":false,"raw":0,"scaled":false,"timing":false,"split24":false,"pps":false}
{"class":"SKY","device":"/dev/ttyUSB1","xdop":0.73,"ydop":0.86,"vdop":0.80,"tdop":1.06,"hdop":1.00,"gdop":2.56,"pdop":1.30,"satellites":[{"PRN":86,"el":24,"az":274,"ss":42,"used":true},{"PRN":73,"el":21,"az":174,"ss":30,"used":true},{"PRN":80,"el":58,"az":113,"ss":23,"used":true},{"PRN":79,"el":31,"az":36,"ss":27,"used":false},{"PRN":69,"el":16,"az":102,"ss":20,"used":true},{"PRN":87,"el":20,"az":331,"ss":35,"used":true},{"PRN":85,"el":3,"az":230,"ss":19,"used":false},{"PRN":71,"el":40,"az":305,"ss":46,"used":true},{"PRN":70,"el":73,"az":47,"ss":0,"used":false}]}
{"class":"TPV","device":"/dev/ttyUSB1","mode":3,"time":"2023-10-26T11:57:45.000Z","ept":0.005,"lat":50.846764767,"lon":4.359011333,"alt":90.200,"epx":10.961,"epy":12.938,"epv":18.400,"track":0.0000,"speed":0.000,"climb":-0.001,"eps":0.21,"epc":0.29}
{"class":"SKY","device":"/dev/ttyUSB1","xdop":0.84,"ydop":0.70,"vdop":0.70,"tdop":1.42,"hdop":0.80,"gdop":3.09,"pdop":1.10,"satellites":[{"PRN":86,"el":24,"az":274,"ss":43,"used":true},{"PRN":73,"el":21,"az":174,"ss":29,"used":true},{"PRN":80,"el":58,"az":113,"ss":23,"used":true},{"PRN":79,"el":31,"az":36,"ss":28,"used":true},{"PRN":69,"el":16,"az":102,"ss":21,"used":false},{"PRN":87,"el":20,"az":331,"ss":34,"used":true},{"PRN":85,"el":3,"az":230,"ss":19,"used":false},{"PRN":71,"el":40,"az":305,"ss":45,"used":true},{"PRN":70,"el":73,"az":47,"ss":0,"used":false}]}
{"class":"TPV","device":"/dev/ttyUSB1","mode":3,"time":"2023-10-26T11:57:46.000Z","ept":0.005,"lat":50.846764783,"lon":4.359011433,"alt":90.200,"epx":12.648,"epy":10.547,"epv":16.100,"track":0.0000,"speed":0.000,"climb":0.000,"eps":25.59,"epc":34.50}
Python GPS data
gps3 is Python package that can be used to retrieve the data from the gpsd daemon. Below is a simple example on how to retrieve the data
First install the gps3 package
pip3 install gps3
GPS date example
from gps3 import gps3
gps_socket = gps3.GPSDSocket()
data_stream = gps3.DataStream()
gps_socket.connect()
gps_socket.watch()
for new_data in gps_socket:
if new_data:
data_stream.unpack(new_data)
print('Alt = ', data_stream.TPV['alt'])
print('Lat = ', data_stream.TPV['lat'])
print('Lon = ', data_stream.TPV['lon'])