Can I use ARM LM3S8962 like a DAQ card?

[Jshu23]

I have the ARM embedded software and have used it to write some programs that run on the LM3S8962.  What I'm wondering is if I can have a program that runs on the PC that "talks" to the ARM board occasionally to query the inputs or control outputs.  If it is possible, how would I do that?

[LV_Pro]

How do you communicate with it now? I am not familiar with this specific set up, but if the development package "talks" to it via the serial port then you can write LabVIEW code that will do the same. If it is talking through the USB it may be a bit more difficult, unless the USB interface appears as a serial port to the operating system of the PC, as some do.

[Jshu23]

The target is programmed through USB, but it doesn't act like a serial device that I can communicate to.  In theory, it would act like an FPGA if I could set it up right, but I don't think the tools exist in the LV environment to do that.  The ARM board would be executing the code it was programmed with and reading the AI while likely doing some signal analysis and occasionally my main PC based program would "request" a reading.  Something along those lines I'm envisioning.  My co-worker did this with the RIO where some of signal acquisition and processing was done with the FPGA and the RIO would execute that routine on occasion.  Does that make sense?

[LV_Pro]

cRIO is set up that way, with actual hardware connections built in, RIO stands for Reconfigurable I/O. There isn't aren't tools in LabVIEW, that I know of, to do this outside of NI hardware. That is why I asked about communicating serially, have it make measurements and communicate them on demand via a "port".

[Jshu23]

I may be able to use the Ethernet on the ARM to do what I want.  Thanks for the responses.

[GoCougs]

You absolutely can use an ARM LM3S8962 like a DAQ card, the only restraints you have are how fast the microprocessor can run and the limited amounts of AI you have available on the Luminary board. you can simply add an AI elemental I/O node to your project and wire your transducer to the luminary board. You then can take the data from the microcontroller and send it to the Host PC through a network published shared variable. There are a couple of tricks to this that may not be completely evident. I have included two links that I think will help you get to where you want to be. The first is setp by step how to connect an accelerometer to teh ARM board, but you can modify it for your own transducer.

http://decibel.ni.com/content/docs/DOC-9614

The second is hwo to use network published shared variables on an ARM board. I hope this helps!

http://digital.ni.com/public.nsf/allkb/6E50B28DDC61C0E68625767400805AA0

Scott W

[Jshu23]

Thanks.  This looks like a solution I am looking for.  Time to start playing around and learning how it works.

Will this work if the PC-based program is an installed distribution assuming I have the right address set up?

[GoCougs]

In order to communicate with the ARM board over shared variables, you will need to have the embedded variable connection manager set up on the PC you are reading it from. This is only included with the LabVIEW ARM module and can only be accessed with the full version of LabVIEW. So if you are using that to send data communication, then you do have to have LabVIEW development enviroment on the PC. If you are using regular TCP communication to send the data, then you could just build it into an executable and it will work as long as you know the IP addresses of target and host (reserved DHCP IP addresses.)

[Jshu23]

Hmm.  I haven't done much with TCP functions.  How would it work if I have the ARM board and I want to send information from it to an installed application running on a PC for which I don't have control over the IP address?  I could code the ARM board to create a TCP connection at some specified address and would I then have the PC application attempt a connection to that same IP?

I'm searching around for other help information on the topic as well.

[GoCougs]

The principles between computer to computer using TCP should be the same as computer to microcontroller. You can find information about TCP/IP comm in LabVIEW here:

http://zone.ni.com/devzone/cda/tut/p/id/2710

Good Luck!

Scott W