Can I use a NI 6722 for 8 channel rbitary waveform generation

[Jez]

Can I use a NI 6722 PCI card (or another card from that series) to generate 8 independent arbitary waveforms. What I want to do is load 8 channels worth of data stored in excel and have the NI 6722 reproduce the signals on the 8 analog output channels.

The signals contain a maximum frequency component of 1kHz and I would like an output between -1.5V to 1.5V.


Thanks for the help

[Raajit_Lall]

Hi,

If you look at the specifications for the 6722 you can output any kind of waveform at a maximum of 800kS/s, and that seems more than enough for your 1Khz signal.  The signals that you are going to be writing to the board are going to be from software and can range from -10..10 V (from the specifications).  The programming of this is very simple as well.  You could use the DAQmx driver.  If you are using that driver you can use an Express VI called the DAQ Assistant to output any values that you need.  You can just create an array of all the data that you want to output and then use the DAQ Assistant or one of the example programs that gets installed with DAQmx to output your arbitrary analog values. 

Each output on the 6722 does have its own DAC (Digital to Analog Convertor), which means that the outputs will be simultaneous and not dependant on each other.  A little bit of programming would be required to get the data from excel and put it into an array which can then be fed into the DAQ example VI or Express VI, but there are plenty of examples for this and should be easy. 

Most of the boards in that class have individual DACs so you should see similar performance and capabilities from those boards.

Hope all of this answers your question.  Please post back if you have any further questions.

Regards,