Graphing input from RS232

[Good_Tweety_Bird]

Yesterday I installed a trial version of LabVIEW because I recall from 7-8 years ago it could easily do what I wanted. I remember from a manual how easy it was to graph data and thought maybe I could put something together but it seems the gray matter in my head has all crept out to make my hair gray and using LabVIEW is not coming back to me as I hoped. One thing I do remember though is that there are lots of examples if one knows where to find them and I remember seeing one where multiple signals were graphed on the same chart.

Here is what I need and I hope you can point me to an example or two.

Data source: FTDI RS232-USB adapter, 115200 baud, 8n1. We use several so I will need com port selection.

Data frequency: Up to 2 transmissions per second, probably 1.

Data description: String of four floating point numbers, range -20.0 to 150.0, can be space or comma separated, \n terminator. Separators and terminator can be changed to whatever is needed.

Presentation:

Four traces with different colors and/or line types.

X-axis: time, Y-axis range of -20.0 to 150.0 or autorange.

History: I would like to be able to see the data real time but also scroll back at least 10 minutes, 20 minutes better, so rolling queues would be ideal. Fixed arrays to hold same amount of data OK. I really have no idea how to connect the array(s) and the display to do this.

I have an existing VI that interfaces with the FTDI adapter so I know that it works. Unfortunately all I have is the executable.

Any examples, pointers thereto, or vi snippets would be appreciated. I am already looking at a few examples but my LabVIEW computer is offline so I must download VIs on one computer then transfer them to the offline machine.

Thanks,

jh

[ogk.nz]

You should still have access to the examples in the Help>Find Examples menu, these are all installed directly onto the PC with LabVIEW install.

That in mind, looking through there if you look at the:

Continuous Serial Write and Read

XY Graph Data Types

Should be enough to jog your memory.

String seperation is easy enough with the Scan from strin given that you know how the data is to be presented.

[Good_Tweety_Bird]

Thanks.

Looks interesting but didn't get far...

Error -1073807202 occurred at Property Node (arg 1) in VISA Configure Serial Port (Instr).vi->Continuous Serial Write and Read.vi

LabVIEW:  (Hex 0xBFFF009E) VISA or a code library required by VISA could not be located or loaded.  This is usually due to a required driver not being installed on the system.

jh

[RavensFan]

Have you installed NI-VISA?

[Good_Tweety_Bird]

Thanks for posting.

I did not. I did not see any obvious way of doing so and assumed it wasn't available with the trial version.

thanks,

jh

[ogk.nz]

What version of LabVIEW are you running?

[Good_Tweety_Bird]

Evaluation version 14.0f1

[Dennis_Knutson]

You just have to download it - http://www.ni.com/download/ni-visa-14.0.1/5023/en/

The fact that you are using the evaluation version is not relevant. You do not mention the instrument you have connected and that is relevant.

[Good_Tweety_Bird]

Thanks, I didn't know what to look for or where to look for it.

I was trying run the Continuous Serial Write and Read example that ogk nz recommended. The only instrument attached is the FTDI USB-RS232 converter I menitioned in my original post.

jh

[Dennis_Knutson]

It just makes no sense to say the only instrument is your converter. That isn't a data source. You've got to have an actual instrument.