Time synchronization
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      How to set up GPS for time and position

      Connecting a GPS receiver via USB to a controller for time synchronization and live position data

      NMEA 0183 protocol

      GPS receivers communicate using several protocols. Of all message standards that are used with GPS receivers, the NMEA 0183 is the most widely used messaging standard. NMEA is the acronym for the National Marine Electronics Association.

      The controller supports the following NMEA sentence codes:

      • $GPRMC (Recommended minimum specific GPS/Transit data)
      • $GPGGA (Global Positioning System Fix Data)

      Controller configuration

      A GPS receiver can be connected to the following controllers:

      • Q.gate (RS-232)
      • Q.pac (RS-232/RS-485)
      • Q.station 101 (USB)
      • Q.station X (USB)

      Q.station X / Q.station 101

      On the Q.station the GPS receiver needs to be connected to the USB port. For GPS receivers with a serial interface, please use a USB to RS232 converter with Prolific PL2303 Chipset.

      Recommended GPS receivers are

                         GPS-ontvanger / u-blox 8 / USB / dakmontage 4,50 m NAVILOCK 62531

       

      The USB-Port configuration is done in test.commander → controller settings → USB devices

       gps3

      The USB device needs to be connected to the correct port on the Q.Station, which is configured in test.commander! No other device can be used on this port. If the device is not connected, Q.Station will have an error state! 

      Read “online state info from controller” to check the correct USB port with test.commander. 

      gps4

      You can see the same information in the “#actual.sta” file of Q.Station. Read the file via FTP using user: “6”, password: “6”

      gps5

      Depending on which type is connected (direct USB or via RS323 converter), the correct protocol has to be selected:

      • NMEA-0183: Serial GPS-Signal via RS232 → baudrate and char-format have to be configured correctly (use Garmin Configuration-Tool to check settings - see Garmin manual)!!
      • Garmin USB-GPS: USB-protocol for direct USB devices → no baudrate and char-format setting necessary.

      Within the controller configuration, the NMEA 0183 protocol has to be selected for the appropriate host interface. When using a Q.staiton X (or Q.station 101), go to Controller settings -> USB Devices, set the Device count to 1, and select NMEA-1083 receiver.

      GPS1

       

      Notes

      • GPS time is in UTC (Coordinated Universal Time), which equals GMT (Greenwich Mean Time) but without daylight saving time. Use a time zone offset to adjust the controller's time to the time zone location it is at.
      • Baudrate (19k2) and Char Format have to be set according to the settings in the GPS receiver.
       

      Time Synchronisation

      To make sure, that the controller receives the signal, there are the following possibilities:

      • Read online state info from controller via test.commander or
      • check #actual.sta file on Controller
        gps6

        If the signal is available and time is set correctly, you can see “SYNC SIGNAL ACTIVE” in “RUN STATES” section (see screenshots above!).

        Also be sure, to have > 0 available satellites seen by your GPS receiver! If not, the signal does not have a valid time information and the controller will not be synchronized. You can check this for example by connecting the sensor directly to your PC and use the Garmin-Configuration tool to get the sensor information (see manual of your Garmin device).

        Or, if communication between Garmin GPS receiver an Q.station is working properly, you can also use arithmetic variables to read the number of available satellites and other information (see GetPositioningData).


        gps7

        Get Positioning Data

        Via arithmetic variables using the function GetPositioningData() it is possible to get some more information out of the GPS-Signal:

        GetPositioningData(Selector;InfoSelector)

        Selector: defines the source (e.g. GPS-Module connected via Host interface RS232 and protocol NMEA-0183)

        • 0 = NMEA via RS232

        On the Q.station it's possible to connect NMEA via RS232 to USB converter. Supported chips of the converters are FTDI, Prolific or Moxa.

        • 100 = NMEA via USB-Port 1
        • 200 = NMEA via USB-Port 2

        If there is a USB-hub connected at USB-port 1 the first port on the hub is 101, the second 102. If the hub is connected at USB-port 2 the first port on the hub is 201, the second 202, etc.


        InfoSelector:

        • 0 = Time
        • 1 = Latitude (degree)
        • 2 = Longitude (degree)
        • 3 = speed in m/s
        • 4 = Heading (0 = north, 90 = east, 180 = south, 270 = west)
        • 5 = numbers of seen satellites
        • 6 = altitude above NN

        For each information, a seperate variable has to be defined. For example:

        gps8 

         

         

        Setup 1

        • Q.station 101 T, FW V1.10 B05
        • Converter USB→RS232 (UGreen with Prolific chipset)+ power supply from a Q.bloxx socket
        • Garmin GPS 16x (RS232)
        gps9

       

      Navilock NL-8004U USB 2.0 Multi GNSS Receiver u-blox 8

      Q.station 101 1.10B05

      Config:

      gps10

      gps11