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robocut
01-24-2009, 04:30 PM
Anyone who knows about a labview-propeller interface.

I know about the BS2--labview interface available at the parallax download area, and i realize that this
code easily could bli implemented in propeller via the 'BS2' object. But,·i guess that the increased serial
power in the propeller could be used for a more effective communication...

I'ts time to dust off my BASIC Stamp powerer robotic lawnmover, RoboCut. It's currently been modified to propeller via a 24-pin propeller stamp.

The current lawnmoving algorithms are quite simple, my plans are to test some more complex navigation/optimazation ideas this spring. To make this easy, my plans are to impplemet at a higher level using Labviev. I will integrate a small netbook , like asus EEEPC in the lawnmover, control this netbook via VLAN by a VNC application. The original RoboCut controller board vill be superseded by the labviev/netbook applikation.

So any labview/propeller experience would be valuable

Greetings from Gothenburg SWEDEN·

Paul Rowntree
01-24-2009, 11:37 PM
@robocut : I have used LabVIEW with the prop over the simulated serial port/PropPlug line; this worked really well, since the LabVIEW serial port drivers under VISA are very robust. I was doing 2 way ASCII communication, never a drop out, never a problem. Is this the interface that you were thinking of?
I had asked Hanno if his ViewProp could be coupled to LabVIEW, and we decided to proceed using a file-based link between these two. Would that be useful?
Cheers!
Paul Rowntree

Post Edited (Paul Rowntree) : 1/24/2009 3:47:16 PM GMT

robocut
01-25-2009, 12:11 AM
@Paul



That sound very useful. I'm planning a 'command based' protokol inspired by prof. Radcliff http://www.parallax.com/dl/sw/labviewbs2.pdf·allowing the labview application to ask for and send digital or analog values.

I'm still not so familiar with labview and it's features for 'parsing' data from strings to realvalues and vice verse...

Is your application available ?

Greetings

Hans Forsberg

Paul Rowntree
01-25-2009, 12:40 AM
@Hans : Thanks for the link to the Radcliff document. My stuff is pretty much the same arrangement, so that you can debug the command codes from a terminal and manually run the prop, then link in the labview code when you have some interesting data to grab or long-term runs to do.

LabView parsing is really easy; they have massive libraries to make life very easy. The only thing that should be attended to is that some form of CRC or string validation should be used to avoid the two ends of the link getting confused, or both waiting for the other to send something on the wire. Especially if working in a noisy area (like an electric lawnmower perhaps?!)

On this I would normally prefer Delphi on the PC, but the serial links of LabView are great and run out of the box. Delphi uses third party modules, and they are a pain.

Sure, the codes are freely available. I will bundle up the various bits into a zip and attach it today. I run LabVIEW 7.1; earlier versions won't be able to read the files (Thanks National!)

Cheers!
Paul Rowntree

Paul Rowntree
01-25-2009, 01:22 PM
@Hans
Here are the two zips : one for the Prop and one for the PC running LabVIEW.
The TOFv1.spin is the most interesting prop code, and the Go routine boots the system then reads characters from the PropPlug and dispatches to the appropriate command routines. THe only controls that are affected by the LabVIEW program are the MCS-related codes. You can drive them from HyperTerm or PropTerm if you do not wan to use the LabVIEW system up front. Each command is 1 letter, perhaps followed by ASCII integers as parameters.

To make this more robust, some error checking on the incoming string should be added, as well as a way to ask the LV program to resend the information.

Good luck, and feel free to ask any questions. The LV code for parsing is fairly clear and clean.

Cheers!
Paul Rowntree