using 2 ni usb 9215 devices to sample 8 channels Simultaneous

[barak]

Hi,

I Need to sample 8 channels Simultaneous using usb devices.

If i use 2 9215 ( 4 channels ) devices in a 9172 chassis i will get acctually 8 channels Simultaneous ?

Does the 2 devices use the same clock?

Is it realy Simultaneous ?

[Ben]

I believe they have to be installed in slot #5 and #6.

See the manual.

Ben

[barak]

Hi Ben,

Thanks for your help,

Can you be more specific?

It's not so clear in the manual.

I just want to be sure it is possible to have 8 samples Simultaneous before i buy the devices.

[Ben]

"

I just want to be sure it is possible to have 8 samples Simultaneous before i buy the devices.

"

If you want to be sure, then don't trust me!

I suggest you call NI directly and when talking to the inside sales rep, ask them to let you talk to support so they can send you an e-mail stating if the operations you need are supported.

Ben

[KyleBryson]

Hi barak,

You can definitely use 2 NI 9215 modules in a cDAQ-9172 chassis to simultaneously sample 8 channels.  The modules can be in any slots (slots 5 and 6 are just for certain triggering applications on digital modules).  You'll need to use them in the same NI-DAQmx task, and they will share a sample clock and sample data at the same time, give or take a few nanoseconds and the specs of the modules themselves.

Calling NI to discuss your exact app is a great idea too.  They'll be able to answer these and any other questions you have.

Regards,
Kyle