Serial port time interval error dotnet c#

[C#ENTHU]

Dear All,
Data comes to my serial port every 6 seconds.
My application is capturing the data @ 1 data/6 seconds initially, properly and converting it into graphs.
But as the time proceeds the capture rate becomes @ 2 data/12 seconds and again after some time @3 data/18 seconds.
At the end of 10 hours its around @ 50-60 data/6 minutes ... and keeps increasing.

MY QUESTION IS : WHY DOES THE TIME INTERVAL KEEPS ON INCREASING AND WHAT CAN BE DONE TO KEEP TIME INTERVAL AT 6 SECONDS?

Please note that no data is lost even though the application comes to a stand-still for 6 minutes.
I have searched various forums for many days without any success.
I am attaching the code and properties settings.

private void Import_Data_Button_Click(object sender, EventArgs e)
{

if (LiveMenu.Checked)
{
LiveMenu.Checked = false;
Live = false;
SPTimer.Enabled = false;

try
{
if (SP.IsOpen) { SP.Close(); }
}
catch { }
}
else
{
{
LiveMenu.Checked = true;
Live = true;
SPTimer.Enabled = true;

try
{
if (!SP.IsOpen) { SP.Open(); }
}
catch { }
DrawGraphs();
}

}

private void SP_DataReceived(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
{
try
{
Serial_Data += SP.ReadLine();
}
catch { }
}

private void SPTimer_Tick(object sender, EventArgs e)
{
SPTimer.Enabled = false;
if (lblLive.Visible == false) { lblLive.Visible = true; }
else { lblLive.Visible = false; }

if (Serial_Data.Contains("\r"))
{
WriteToDatabase(Serial_Data);
Serial_Data = "";
}

SPTimer.Enabled = true;
}

Any suggestions will be of great help to me.

Thanks!!!
Rupali

[Momerath]

Have you verified that the SPTimer_Tick is firing at a constant rate? Have you checked if there is something in Serial_Data each time it fires but that there is no '\r' character in it?

This might also be the problem (from the documentation):
The DataReceived event is not guaranteed to be raised for every byte received. Use the BytesToRead property to determine how much data is left to be read in the buffer.

[C#ENTHU]

Serial port properties attached

dear all,
data comes to my serial port every 6 seconds.
My application is capturing the data @ 1 data/6 seconds initially, properly and converting it into graphs.
But as the time proceeds the capture rate becomes @ 2 data/12 seconds and again after some time @3 data/18 seconds.
At the end of 10 hours its around @ 50-60 data/6 minutes ... And keeps increasing.

My question is : Why does the time interval keeps on increasing and what can be done to keep time interval at 6 seconds?

Please note that no data is lost even though the application comes to a stand-still for 6 minutes.
I have searched various forums for many days without any success.
I am attaching the code and properties settings.

Private void import_data_button_click(object sender, eventargs e)
{

if (livemenu.checked)
{
livemenu.checked = false;
live = false;
sptimer.enabled = false;

try
{
if (sp.isopen) { sp.close(); }
}
catch { }
}
else
{
{
livemenu.checked = true;
live = true;
sptimer.enabled = true;

try
{
if (!sp.isopen) { sp.open(); }
}
catch { }
drawgraphs();
}

}

private void sp_datareceived(object sender, system.io.ports.serialdatareceivedeventargs e)
{
try
{
serial_data += sp.readline();
}
catch { }
}

private void sptimer_tick(object sender, eventargs e)
{
sptimer.enabled = false;
if (lbllive.visible == false) { lbllive.visible = true; }
else { lbllive.visible = false; }

if (serial_data.contains("\r"))
{
writetodatabase(serial_data);
serial_data = "";
}

sptimer.enabled = true;
}

any suggestions will be of great help to me.

Thanks!!!
Rupali

[C#ENTHU]

Thanks for your reply!

The data comes properly when viewed on hyper terminal i.e. @1 data/6 seconds, continously. Also all the data contains "\r", as the data is never lost and only the time interval of importing into app and drawing graphs keeps increases.

I have also attached a snapshot of properties please view.

Also "Drawgraph" doesnt take more than 6 seconds as initially the refresh rate is @1 data/6 seconds for some time(say half and hour).

Kindly reply if you have any suggestions.

Have you verified that the SPTimer_Tick is firing at a constant rate? Have you checked if there is something in Serial_Data each time it fires but that there is no '\r' character in it?

This might also be the problem (from the documentation):
The DataReceived event is not guaranteed to be raised for every byte received. Use the BytesToRead property to determine how much data is left to be read in the buffer.