Moving Map

See also -  Moving Map Control  Moving Map Menu  Configuration

Introduction

When your GPS is connected directly to a computer and the GPS is sending the NMEA $GPRMC or ($GPGGA and $GPVTG) or ($GPGLL and $GPVTG) sentence OziExplorer can plot your location directly onto the map on screen in real time, this is called "Moving Map". You must have a calibrated map available which covers the position the GPS is sending.

Software Simulator - For testing, a software simulator is provided in OziExplorer and details on how to use this are provided below.

Moving Map has the following features.

Setting up Maps for Use with Moving Map

When you move off the current map OziExplorer will search through the available maps and select a map which can show the GPS position and provides the best scale. If a suitable map cannot be found OziExplorer will wait 15 seconds and search again, then 30 seconds and search again and then 60 seconds between searches.

Maps are setup for use in Moving Map by default. If necessary, changes can be made in the map calibration screen. See the Moving Map Options of the Creating Maps help for details and explanation.

GPS Setup

To use moving map your GPS must output certain NMEA sentences in the 0183 format. The required sentence(s) are :

Most GPS receivers can output the required sentences but most require configuring. You may need to refer to your owners manual for the method.

Some Garmins have the capability of outputting the required information using the PVT format, this is also supported by OziExplorer and this option is turned on in the Comm Tab in Configuration.

The GPS needs to be connected to the USB or serial port of the PC. Other GPS types, such as bluetooth, use driver software to install a virtual serial port.

Starting Moving map

If you have everything setup correctly Moving Map can be started by selecting the Start NMEA Communication with the GPS option on the Moving map Menu. Alternatively (and preferred) you can activate the Moving map Control and press the Start button.

If it is working ok you should see some indication on the Status Line at the bottom of the map. See the Status Display section below.

If it is not working as expected see the Trouble Shooting section in the Help Index.

Command Line Parameters

To allow moving map to be automatically started when starting OziExplorer the following command line parameters are available. Note, the / is part of the parameter name.

The following command line parameters can be used when starting OziExplorer

/mmstart - Starts Moving Map (NMEA) communication
/mmcontrol - Shows the Moving Map Control
/navcontrol - Shows the Navigation Control
/gpsfix - Shows the GPS Fix window

example  command lines
oziexp.exe /mmstart /mmcontrol /navcontrol /gpsfix
oziexp.exe /mmstart
oziexp.exe c:\oziexplorer\maps\mymap.map /mmstart /mmcontrol

Note that you can specify a map on the command line but if the GPS position is not on that map or the map has not been specified as available for Moving Map OziExplorer will attempt to find a new map.

Status Display

The status line at the bottom of the screen displays the following.

The left hand panel will show "Moving Map is ON" when you start the NMEA communication. It does not have to be receiving data from the GPS to display this message. The panel will show a <+> symbol which will toggle on and off when actual data is being processed. If you see the plus sign it means the correct data is being received and processed for display on the map, if you do not see the <+> symbol something is not right. If the <+> symbol is not being toggled on and off data is not being processed.

The next panel will display the following, these should be toggled on and off when data is being received.

There a 2 little lights that flash. The left hand light will flash blue and white when NMEA sentences are being received. The right hand light will flash green and white when a suitable NMEA sentence is being processed and the data is valid, it will flash red and white when the data is invalid (the gps may not have a fix or it may be in simulator mode).

The right panel displays the position of the GPS.

The time displayed to the right of the position is the PC time the last position was received, this indicates how old the position fix is.

The Track

Track Tail - If the Log Track Tail option is ticked on the Moving Map Menu the track will be displayed by Moving Map and this is called the Track Tail. It is a track of 10,000 points. If the maximum is reached, the first track points collected drop off as needed. To turn on/off the display of the Track Tail, tick/untick the Log Track tail option on the Moving Map Menu.   Note : Even with the Log Track Tail unticked, if the Log Track to File option is ticked, all track points will still be stored in a file on the hard disk.

If the Log Track to File option is selected on the Moving Map Menu then the track is automatically captured can stored to file. The track log can be stored to different files Daily, Weekly, Monthly or Never. The default setting is Daily. Never means a different file is never created (see below).  This setting is configured on the Track tab in Configuration. A new file (based on the date and time) will be created daily, weekly, monthly as required.

If the Never setting is selected for the file frequency and the Log Track to File option is ticked on the Moving Map Menu, the track will be automatically saved to a file mmTrack.plt (or a name you specify). The track is always appended to this file even when starting new moving map sessions and the file will keep growing in size. An option is provided on the Moving Map menu to clear this file. The track file mmTrack.plt (or the file you specify) is a normal OziExplorer track file and can be loaded and displayed on a map as normal. Each moving map session is treated as a separate track segment. To change the file name (mmTrack.plt), use the option Change Track Log File on the Moving Map Menu.

See the Moving Map tab on the Configuration dialog for setting up the intervals at which the track points are captured and stored. The configuration help has details on this feature. Note - capturing of the track is disabled when the interval is set to zero (0).

The track log files can be loaded and saved the same as any track, and it can be loaded and saved at any time to any name.

The time collected and stored for a track is the UTC time extracted from the NMEA sentences but the date used is the PC date. This is necessary as not all NMEA sentences provide the date. Note that the time initially used to log track points may be the PC time until a time has been collected from the NMEA sentence.