list devices in ni-daqmx Dev1 in c

[Andrzejsz]

Hi,

I'm trying to control multiple USB 6501 devices devices from a linux machine using standard C. I would basically like to be able to get the output of lsdaq in the code, i.e. to associate the serial number with the Dev1,Dev2,...names.

I have looked at the:

vxipnp/linux/NIvisa/Examples/C/General/FindRsrc.c 

and this works however it only gives me the following string:

USB0::0x3923::0x718A::015C400E::RAW

whereas lsdaq looks like:

NI USB-6501: "Dev1"    (USB0::0x3923::0x718A::015C400E::RAW)

so, as I said, I'm missing the Dev1 - serial number connection.

If the devices were discovered by the visa methods in the same order as in lsdaq, I guess I could hardcode it, but they're not. Also I would probably prefer using nidaq-mx(-base) methods to do this if they exist.

thanks,

Andrzej

[Courtney_L]

Hi Andrzejsz, 

I came across this command from another forum:

In C, we can use "Get/Set/Reset Dev_ProductNum" to get the device product number.

int32 __CFUNC DAQmxGetDevProductNum(const char device[], uInt32 *data);

For USB 6211

Device ID	Device Name
0x7270	NI USB-6211

This is for DAQmx (and not base) but I will do more research and see what else I can come up with for DAQmx-base. Is this on the right track? So far I haven't found any specific DAQmx-base command for device name.

Keep me posted with any further developments.

Courtney L

Applications Engineer

National Instruments

[Andrzejsz]

Hi Courtney,

thanks for your reply. I think I could use Daqmx - at least other parts of my code compile.

Anyway, I tried the function you suggested:

 id11=DAQmxGetDevProductNum("NI USB-6501", &id1);
 id21=DAQmxGetDevProductNum("Dev2", &id2);
 id31=DAQmxGetDevProductNum("Dev3", &id3);

 printf("ids found: %d , %d, %d \n",id1,id2,id3);
 printf("ids found, hex: %x , %x, %x \n",id1,id2,id3);

I get:

ids found: 0 , 0, 0
ids found, hex: 0 , 0, 0

When I try lsdaq, I get:

Detecting National Instruments DAQ Devices
Found the following DAQ Devices:
NI USB-6501: "Dev1"    (USB0::0x3923::0x718A::015C400E::RAW)
NI USB-6501: "Dev2"    (USB0::0x3923::0x718A::01646B0B::RAW)
NI USB-6501: "Dev3"    (USB0::0x3923::0x718A::01646C0A::RAW)

I tried using "DevX" names, because that's the syntax I found here:

http://forums.ni.com/t5/Multifunction-DAQ/How-to-use-DAQmxGetDevProductNum-and-DAQmxGetDevProductCat...

but I tried the "NI-USB-6501" just in case.

So, no go for the time being.

thanks for your help,

Andrzej

[Andrzejsz]

I found another function, which I think in principle should do exactly what I want it to (below),

however this still gives zeroes in the second parameters. If I were able to get this one working this would solve my problem.

The problem is I can't find a description of any of these functions in the .html documentation provided with the NI install CD.

Andrzej

int32 __CFUNC DAQmxGetDevSerialNum	(	const char	device[],
		uInt32 *	data
	)

[Andrzejsz · Accepted solution]

Ok. I went back, looked through the NIDAQmxBase.h

and found:

DAQmxBaseGetDevSerialNum(const char[], uInt32 *);

this works for me, i.e. if I assume the total number of boards I can retrieve their serial numbers and work with that.

It would be nice if there was at least a hint of this function in

/usr/local/natinst/nidaqmxbase/documentation/

Andrzej

[Courtney_L]

Hey Andrzejsz,

I'm worried about your compatibility with DAQmx. You're using Linux with NI USB devices, correct? From what I can tell that shouldn't be compatibile with DAQmx. Take a look at this link: 

http://zone.ni.com/devzone/cda/tut/p/id/3695#toc0

If this isn't the problem I will definitely keep digging for documentation! 

Courtney L

Applications Engineer

National Instruments

[Andrzejsz]

Hi Courtney,

thanks for your reply. Indeed I was using nidaqmx-base before and only switched to nidaqmx to test your suggestion. I have found a solution using nidamx-base (see above), so you needn't worry about looking for further documentation.

thanks,

Andrzej

[Courtney_L]

Hey,

Great -- glad you solved it! I didn't see your post before refreshing my page :). Yes - as a fellow DAQmx-base user (mac) I agree the documentation could be better. I'll put in a request on my end to alert the team to the problem!

Courtney

[Courtney_L]

Hi there,

I wanted to let you know I filed a request to have this documentation looked at so hopefully it will be improved for future users.

Thanks for bringing this to our attention!

Courtney L.

Applications Engineer

National Instruments

[Emna]

hello 

Can I connect 4 cards 6518 to one office PC 

please any one can help me

thank you for the help