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Enhanced GPS Sample Update

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14 Jun 2010CPOL 16.4K   1   8
The modded MS GPS_Sample application with the addition to support streamed serial raw GPS data like that available on Intermec CN50

Sometime ago, I published my modded GPS_Sample code (see here), which is based on a Microsoft GPSsample.

This time, I added support for Int*rm*c CN50, which does NOT support reading raw GPS data using a serial connection. Instead the CN50 streams the data to the ‘communication’ port.

BTW: did you know how easy it is to create skins for use with MyMobiler?

The stream reader part is outsourced into a thread, which is based on my background thread class bgThread2 (see this link). It was very easy to implement the stream reading within the thread, so the GUI is not blocked during read waits.

C++
#region TheTHREAD
private void myThreadStart()
{
    System.Diagnostics.Debug.WriteLine("Entering thread proc");
    int _i=0;
    try
    {
        do
        {
            //The blocking function...
            char[] cSep = new char[] { '\r', '\n' };
            int iRes = 0;
            do
            {
                string sRes = "";
                iRes = GPS_Sample8.ReadFileClass.readFile(_sCOM, ref sRes);
                string[] sAll = sRes.Split(cSep);
                foreach (string s1 in sAll)
                {
                    SendData(bgWnd.Hwnd, iRes, s1);
                }
                //Application.DoEvents();
                Thread.Sleep(100);
            } while (iRes == 0);
            
            System.Diagnostics.Debug.WriteLine("Thread sleeps...");
            _i++;
            Thread.Sleep(100);
        } while (bRunThread);
    }
    catch (ThreadAbortException)
    {
        System.Diagnostics.Debug.WriteLine("Thread will abort");
        bRunThread = false;
    }
    catch (Exception ex)
    {
        System.Diagnostics.Debug.WriteLine("Exception in ThreadStart: " + ex.Message);
    }
    System.Diagnostics.Debug.WriteLine("ThreadProc ended");
}
#endregion

The main form code has some new functions to check for iCN50 and start/stop the stream reader background thread:

C++
#region CN50raw
bgThread2 myStreamReaderThread;
private void OpenStream()
{
    //background thread already running?
    if (myStreamReaderThread == null)
    {
        string szPort="";
        szPort = GetGPSPort();
        if (szPort != "")
        {
            //start a new thread
            myStreamReaderThread = new bgThread2(szPort);
            myStreamReaderThread.bgThread2Event += 
	       new bgThread2.bgThread2EventHandler(myStreamReaderThread_bgThread2Event);
        }
        else
            AddRawText("No raw GPS port found");
    }
}

void myStreamReaderThread_bgThread2Event(object sender, bgThread2.BgThreadEventArgs bte)
{
    AddRawText(bte.sString);
}
private void CloseStream()
{
    if (myStreamReaderThread != null)
    {
        myStreamReaderThread.Dispose();
        Application.DoEvents();
        myStreamReaderThread = null;
    }
    Application.DoEvents();
    mnuRAWStart.Enabled = true;
    mnuRAWStop.Enabled = false;
}
#endregion

Download (VS2008 Solution Targeting WM6 SDK)

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


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Comments and Discussions

 
GeneralWhy some delay (not always) Pin
jozeunico27-Jul-12 8:46
jozeunico27-Jul-12 8:46 
GeneralRe: Why some delay (not always) Pin
hjgode27-Jul-12 19:04
hjgode27-Jul-12 19:04 
GeneralRe: Why some delay (not always) Pin
jozeunico30-Jul-12 5:52
jozeunico30-Jul-12 5:52 
GeneralRe: Why some delay (not always) Pin
hjgode30-Jul-12 6:52
hjgode30-Jul-12 6:52 
GeneralRe: Why some delay (not always) Pin
jozeunico30-Jul-12 8:14
jozeunico30-Jul-12 8:14 
GeneralRe: Why some delay (not always) Pin
hjgode30-Jul-12 17:55
hjgode30-Jul-12 17:55 
GeneralRe: Why some delay (not always) Pin
hjgode21-Nov-12 4:54
hjgode21-Nov-12 4:54 
I am sorry, but I dont know the internals of qualcomm GPS. I assume XTRA will enable any way to receive almanac data faster, but who knows.

For MS GPSID this is all transparent and invisible.
GeneralRe: Why some delay (not always) Pin
jozeunico21-Nov-12 4:58
jozeunico21-Nov-12 4:58 

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