Support of a MSP430 evaluation board in LabView

[Dennis_Knutson]

Check out http://forums.ni.com/t5/LabVIEW/Nugget-1-of-n-GEtting-started-with-USB-communication-via-VISA/m-p/74... and the subsequent nuggets. Study USB at www.USB.org.

[Sam_Sharp]

The link that Dennis_Knutson refers to only applies if you actually want to communicate with the device using the USB protocol, rather than a device that enumates a serial (COM) port when plugged in. Look at the NI-VISA Serial examples for information - there's a very simple example here for sending a command and receiving a response from a serial port. This would be much easier than trying to use the USB protocol.

I also think that writing code for a microcontroller to act as an intermediary between LabVIEW and your DAC Eval board is excessive and unnecessary - use a USB Analogue Output device that has LabVIEW drivers (for example - an NI board) or if you must use that DAC Eval board, then get a USB to SPI adapter.

[Dennis_Knutson]

The op did ask how to interface to USB when no driver exists. I hope the link I provided shows how complicated this can be and is not for the faint hearted.

Also, isn't the Meilhaus devices rebranded Measurement Computing devices? The process seen comparable to NI's as well.

[Pavel_47]

Thanks for suggestions,

I think the simplest solution would be to use FTDI module that realize SPI over USB (about 10 ... 20$)

I've already used it for CC2538 dev. kit card (from TI) and it works perfctly (but only in MASTER mode)

I hope that there is some SPI cofigurable block inside LabView, isn't it ?

This way LabView can write to such "SPI block", MSP430 card will read the LabView message (with help of SPI interrupt) and using "autentic" SPI will retransmit the data to DAC board.

Concerning Meilhaus devices ... they are slightly cheaper thant theirs NI counterparts and also Meilhaus is situated in Europe, so the delivery is more rapid (we are in Switzerland)

Thanks once more

Pavel

[GerdW]

Hi Pavel,

Concerning Meilhaus devices ... they are slightly cheaper thant theirs NI counterparts

Yes, they are cheaper.

But: they bring their own driver, while NI devices are supported by DAQmx. And when it comes to features and manufacturer support you're definitely better with NI products…

In summary: when calculating TCO you should keep in mind the time needed to handle problems, when the driver isn't doing what you want it to do!

I don't want to express that Meilhaus provides "bad" products, but I heard a lot of problems because of the hardware driver they provide for LabVIEW users…

Meilhaus is situated in Europe

A lot of NI DAQ hardware comes from Hungary…

[Dennis_Knutson]

No, you will have to write your own spi code unless you use one of the NI spi devices.

Time to download LabVIEW and start taking the free tutorials.

[Sam_Sharp]

The FTDI modules have a LabVIEW wrapper/driver available from the FTDI website - I think you need to use it in D2XX mode. Or you can call the library functions directly from the DLL.

Why are you still wanting to use a microcontroller? Why don't you talk to the DAC card directly?

[Pavel_47]

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@Dennis_Knutson wrote:
No, you will have to write your own spi code unless you use one of the NI spi devices.

Time to download LabVIEW and start taking the free tutorials.

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Probably I missed something ... otherwise how to "catch" SPI burst at mcrocontroller board side (e.g. MSP430 eval board) without writing dedicated code for this board.

I've just installed LabView. During installation I've selected only 64-bit LabView module and not 32-bit modules (english/french/german/etc.)

As result many other modules couldn't be installed as they required 32-bit LabView module.

Moreover Measurement & Automation module were installed in German !

So everything to be reinstalled.

Pity ... as the installation continued about 3h.

Regards

Pavel

[Pavel_47]

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@Sam_Sharp wrote:

The FTDI modules have a LabVIEW wrapper/driver available from the FTDI website - I think you need to use it in D2XX mode. Or you can call the library functions directly from the DLL.

Why are you still wanting to use a microcontroller? Why don't you talk to the DAC card directly?

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Sam,

Here I talked about a "very low-cost" solution: "micoprocessor module, e.g. MSP430-based (about 50$) + DAC card (about 20$) + cables" doesn't surpass 100$.

In such case the DAC card has only SPI interface.

Once FTDI module is properly installed (using accompagning software), LabView can access to all DLLs isn't it ?

Regards

Pavel

[Dennis_Knutson]

If you are going to use custom hardware such as the ftdi converter, you have to write custom software to use it. The ftdi examples are pretty low level. If you were to use National Instruments spi hardware, you wouldn't have to write so much custom code. If you were to use the MSP430, you have to write spi code that runs on the micro and custom serial code that runs on the micro.

I would suggest just installing the 32-bit version.