Voltage level into Oscilloscope waveform

(This is a re-post of the thread that i posted on Dec 2nd, 2009, 11:49 PM )

Hello. I have another enquiry and need guidance on the following :


As mention in another thread ( if you have came across it --> Getting voltage from RS232 & allow dial voltmeter to point according to voltage level ), my circuit board is connected to solar cell and also a power supply(those laboratory DC power supply used in schools) and its connected to the computer via a RS232 Serial cable port.

Thru the serial cable port, a voltage level is sensed and is displayed on the "Voltage Level in Volts(V)" -- See attach image

With the help and suggestions from people in VB forum, i am able to display a Dial Voltmeter with a needle.

As for now, i am also needed to display the voltage level into another type form intead of just Dial Voltmeter.

Maybe to display the voltage level to a waveform like what we see on the oscilloscope ? I came across a suggestion from someone regarding the oscilloscope, but its in C# instead, and after converting, the codes does not work. Hmm.. ?

>> Therefore, i hope to get some guidance on how to display the voltage level into a waveform as what we see on the oscilloscope.


>> Please also feel free to voice out any other suggestions you have in mind other than oscilloscope waveform ? Once again, if any of the above is unclear, please inform me.
Thanks in advance.

Why did you re-post your question? There is never a reason to re-post the exact same question.

@weirddemon

As the previous post was posted on 2nd dec, and today is already the 7th dec, i've yet to get any guidance or solutions regarding my thread .
Therefore i decided to re-post , as it'll appear under the new post which i thought will attract more attention as i need the solution asap.

Yup..thats the reason why. Hope you understand.
I apologize if by doing so has broken any rules or have cause any inconvenience to any one. :)

Quote:

---

Originally Posted by catherine0136

@weirddemon

As the previous post was posted on 2nd dec, and today is already the 7th dec, i've yet to get any guidance or solutions regarding my thread .
Therefore i decided to re-post , as it'll appear under the new post which i thought will attract more attention as i need the solution asap.

Yup..thats the reason why. Hope you understand.
I apologize if by doing so has broken any rules or have cause any inconvenience to any one. :)

---

Again, there are no reasons to re-post. It only clutters up the forum.

Just post a response to your thread, asking for additional help, and it will jump back to the front of the forum. This is called BUMPing (Bring Up My Post) the post. However, please do not arbitrarily BUMP your post.

If you're not receiving any responses, it's probably because what you're asking is either not phrased the correct way, what you're asking is unclear, or you haven't provided enough information.

Also, it's helpful to post relevant code and what you've already done. People are sometimes unwilling to help those who appear to be just looking for copy and paste code. If you've done any work in trying to resolve this on your own, mention that and post any relevant info.

Code:

---

Just post a response to your thread, asking for additional help, and it will jump back to the front of the forum. This is called BUMPing (Bring Up My Post) the post.

---

Actually i didnt realise about it till you mention. Haha. Thanks for the information. =)

Will take note of the other things you mention. :)

Catherine,

First, how rapidly is the data sent from your RS-232 board (samples per second)? I assume that you already have this part working?

Second, there are a couple of ways to handle the OScope charting. You can draw the cart onscreen just like the dial, but handle the update a little differently (take a look at my PC Data Acquisition pages (www.mvps.org/rgrier under Serial Port/DI-194 for a view of how I solved this problem by drawing using similar techniques that were shown two you in the meter code that you've already got running). I also show a display that uses the Mooseworks Instrumention control. You Your application may have similar requirements. Download the paper that I provide there, it has some more information. I provide the source code for this in my book, but if this looks like something that would be helpful, you can send me email and I can send you a ZIP that shows how it is done.

However, there is another alternative. You might use the free MSChart control that you can download from http://www.microsoft.com/downloads/d...displaylang=en). Depending upon the update (sample) rate, this control might be fine. For example, the Series.ChartType.Spline or Series.ChartType.Line might work well. The only code required then is load the data into the chart object itself, and let it work its magic. There are examples online for most situations (see: http://code.msdn.microsoft.com/mscha...ReleaseId=1591 for examples).

Dick

Thank you DickGrier for your time in responding. =)

Will get back to you again by tomorrow if i need more help , or if theres anything which i dont understand. :)

Based on the indication from your previous posts that the only information being provide to the program is voltage level, then clearly the only type of voltage being measured is DC (Direct Current). Your wave form will be a horizontal line measured over a period of time. Chart plotting of a horizontal line is much easier than trying to produce a sine wave on a chart.

@TokersBall_CDXX
Thanks for your suggestion. Will take note and consider about it.


In the mean time, i hope to receive most suggestions / guidance from everyone. Thanks in advance. :)