drawing a real time line chart 1

[garwain]

I have a program that captures data in real time from the serial port, and I need to find a way to plot the points onto a chart in real time. I've spent several hours trying to figure out the mschart component, without success.

I would appreciate it if someone could point me to an example that will actually plot each point and connect it to the previous.

My data would consist of a reading every 250ms of the elapsed time, and a pressure reading.

Unfortionatally I don't have any budget to purchase components, but if anyone knows of a free component for VB6 that will do this easier than mschart I'd be happy to try it.

Any suggestions are appreciated

 

[zemp]

I often use an ocx control that I found on the web called 'Graphlite'. By Sam Hugill (forgive my spelling if it is incorrect) I think. I can't remember where I got it but a search with Google should get you some results.

Take Care,

zemp

"Show me someone with both feet on the ground and I will show you someone who can't put their pants on."

 

[DaShamus]

garwain, have you found anything yet? I've been looking around for an almost identical project with no luck...

Sean

 

[strongm]

Using the chart control for doing a line plot is about this easy:

Dim myChartData(5, 1) As Variant ' 6 readings for 2 data series
Dim lp As Long

MSChart1.chartType = VtChChartType2dLine
For lp = 0 To 5
myChartData(lp, 0) = Rnd * 10
myChartData(lp, 1) = Rnd * 20
Next

MSChart1.Chartdata = myChartData

 

[DaShamus]

Thanks! Do you know how to stop it flickering when you update?

Sean

 

[DaShamus]

Sorry! I'll rephrase that a bit better. It's late and I'm tired. What i need to do is to read 2 values from an instrument on the RS-232 port (Done and working to a CSV) I now need to try and make it plot to a MSChart graph in realtime. I've got all the data in an array (up to 32 000 depending on scan size)

Thanks

Sean

 

[strongm]

The LockWindowUpdate API call may be your friend here