Wednesday, 11 April 2012

Cheap plotter.. update....

Just a brief update to bring my last post up to date...  the following may help someone who comes along and experiences similar issues...

So...
  • For Christmas I bought myself a Netbook - make and model probably immaterial but it's an HP Mini 210 which I chose primarily on battery life. More importantly it's running Windows 7 Starter (which is a 32bit operating system - Windows 7 Starter can only be 32bit, this is important later..)
    Not my hands but this gives you an idea
    of the size of the notebook..


  • For £10 I doubled the memory from 512Kb to 1Gb RAM, again probably immaterial, but I take the view it can only help...
  • Plotter software, based on feedback on the Practical Boat Owner forum [clicky] I decided to go for OpenCPN [clicky] - it's free and open source, and is constantly being developed, and the version I started with was v2.5.0... Check the web site for the latest stable version, as almost certainly I'll be on a later level than this post...
  • OpenCPN then needs charts - charts for OpenCPN are difficult to source as there are currently (at time of writing - since then I believe VisitMyHarbour [clicky] have made a set available)  no UK charts available to buy in the correct format - you have to search the web for a suitable download (I Googled "CM93"); the set I found are old'ish - 1993 - but as a backup to my proper paper charts they'll do... they are also vector format ie. digital charts that allow you to set layers of data over the original display...

    Example Vector Chart from http://celebrating200years.noaa.gov/
    NB. According to the chap from the VisitMyHarbour site, they will be producing a set of OpenCPN compatible charts later this summer which would definitely be on my "buy list"..the advantage for me is that one they will be more up to date, two they will be legal, and three they are in raster format ie. non-digital, basically a straight scan/copy of a paper chart - in this case the Admiralty charts that most UK based sailors recognise (and I prefer to the vector format). There isn't the same ability to zoom (if you zoom in to close they blur) but the charts are more useful to me and I don't need the full digital functionality anyway.
  • So - with charts downloaded, file them in the OpenCPN charts folder - when you start OpenCPN you need to tell it where your charts are, and it should then start up with the relevant chart loaded and your position indicated by a black boat symbol - first time this will be at latitude 0 longitude 0 (the default when no GPS is attached...)...
  • Next step, set up your GPS - originally I used my Garmin GPS72, but I've now bought a dedicated GPS satellite receiver - I'm using a GlobalSat BU 353 (right - and approx £20 from eBay)  Before plugging it in, follow the instructions in the box and find and load the drivers for the GPS, also download a program called GPSInfo which you can get from the same website.. I got my versions of these direct for the web site as I assumed these would be newer than the one's on the CD in the box.
  • Next - and don't struggle, just trust me on this - source a free application called XPORT [clicky] and download it. Why do you need it?? Two main reasons.. 
    1. XPORT is a virtual COM port splitter - what's that?? It allows multiple applications (like OpenCPN, and GoogleEarth, and  etc etc) to use the same GPS - if you don't have it you can only use one application at a time.
    2. It allows you to predefine a COM port for the GPS and irrespective of whatever port Windows then decides to give it (which can change every time you plug it in, and whichever USB port you use) you always know the GPS is on a specific port
    3. I have no idea why - but I also found that it stopped my GPS from timing out in OpenCPN every 15 minutes or so...
    4. OK so that was three....but hey...  Oh, and the 32bit is important because XPORT only runs on a 32bit version of Windows...
  • Next plug the GPS in - it'll show a solid red LED while it's searching for satellites - once it starts to flash, it's found them. Then (and only then) start XPORT. When starting XPORT, if it's currently installed there will be no window, just a tray icon. Double-Click on the tray icon to open the configuration dialog (that's it, right). Scan for your GPS or set the input port manually if you already know (you can find it via the Control Panel), and set the output to an unused COM port on the right, make sure the Baud rate is set to 4800 (which is the BU353 speed) then hit "Enable Ports" and it's ready to go. You can now close the dialog as XPORT will continue to run in the task bar and will start when Windows starts. The XPORT web page explains all the other fields..
  • You can now start OpenCPN; when you have select the toolbox icon on the menu, and select the GPS tab - set the COM port as the one you set in XPORT (the unused one you set on the right), set the Baud Rate to 4800 (not sure if you need to do this here as well as you set it in XPORT, but hey ho no harm done), and I always check the "NMEA Window" option as I like to see the GPS talking to ensure its working - click OK, and you should appear as a red ship icon on the OpenCPN screen on the relevant chart ... See following.... which shows me as being moored inland as that was where I happened to be with the GPS at the time...  you can also see the NMEA conversation window (labelled COM2) and also a sample of the vector charts that OpenCPN uses

  • If it doesn't show that - or the ship icon is black, or the NMEA window doesn't show any "chat" then there may be a problem with the GPS - this is where you can use the GPSInfo program you downloaded above - GPSInfo is a simple interrogation tool that you can use to check your GPS is working - us it in conjunction with the LED light on the side of the GPS to find out whether the GPS is working...
...and that's it!

Feel free to drop me a comment if you have any questions and I'll see if I can help...

4 comments:

  1. Great explanation. Thankyoiu. Do you know if it all works on XP? I have an eepc netbook running xp - no cd drive though.

    Cheers
    JohnB
    Poole

    ReplyDelete
    Replies
    1. John - I can't think why not ... I only have direct experience of doing this under Windows 7 Starter, but all the applications and hardware will run under XP

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    2. PS. Note the comment about 32 bit version of Windows though - from memory I think you can install Windows XP in 16 or 32 bit mode..???

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