Pulse generation using 6036E DAQ card !

[morpheus007]

hi!
i need to generate a train of 8 pulses: sine as well as biphasic pulses using 6036E DAQ card. can somebody give me a headstart into what i should be looking at. do i need to use analog output or counter output for the purpose. thanks in advance.

[pkripak]

I have worked with the 7030E DAQ card. I dont know exactly how it is different from the 6036E. We used the "AO Generate Waveform" VI along with other VIs like "Sine Waveform" and "Triangle Waveform". The former generates the waveform given the waveform data that is generated by the latter two VIs and DAQ information - namely, device and channel details.

Prakash K

[morpheus007]

Thanks prakash..i guess this should work with 6036E too. however i am not sure as to what to put down as the "device number" in the AO Generate Waveform.vi. the help section says that it is the "device number you assigned to the DAQ device during configuration".
thanks once again!

[pkripak]

The device number will be available in MAX (measurement & automation explorer). The device will be assigned a default number which you can use for the VI.

Prakash K

[morpheus007]

Thanks! is there a way to get the DAQ output all the way to zero,when i stop the vi. the DAQ output hangs at the voltage level at which it was stopped and continues on at that voltage.
2)I observed the waveform on the oscillioscope and the output for "Sine Waveform.vi" is not exactly sine. The output seems to be clipped and more resembles a square wave rather than a sine. i tried increasing the sampling frequency, but of no use.
3)the stop button does not actually stop the vi at high sampling frequency and high number of samples. i had to invariably hit on abort to stop the vi. why is this so.

[pkripak]

1. You may have to manually append the signal with zero values. I have not really faced such a situation.

2. I cannot see why the sine waveforms are not generated. Maybe, the amplitude of the generated waveforms are very high and they get clipped off in the oscilloscope.

3. It is probably because labview is busy generating the waveform data and is not able to respond to the stop action.

Prakash K

[morpheus007]

thanks prakash for all your help. i really appreciate this.
how could i manually append zeroes to the signal?

[pkripak]

Actually, I misunderstood your question. All you need to do is to set the "reset signal" input in "sine waveform" VI to true. That should take care of this problem.

Prakash K

[morpheus007]

I am also trying to use Generate Pulse Train.vi. However i am not sure as to what to put down for the taskID for counter and counter-1 as well as the counter input for the VI. The 6036E DAQ card has two counters:Counter 0 and Counter 1.

[LYu]

Hi morpheus007,

It sounds like you've bugun your development using the Traditional DAQ driver. Depending on which version of LabVIEW you're using, you can make use of the newer DAQ driver (DAQmx) for your data output. The LabVIEW shipping examples provide a good starting point. You can access the examples by going to Help >> Find Examples. In the "Browse" tab, you can try the following examples:

If you need to continue using the Traditional DAQ driver,
Hardware Input and Output >> TraditionalDAQ >> Analog Output >> Function Generator.vi
This example will show you how you can output different data types. This example outputs continuously, hence you can check out some of the finite generation examples for your application.

If you can use the DAQmx driver,
Hardware Input and Output >> DAQmx >> Analog Generation >> Voltage >> Gen Mult Volt Updates - Data Types Example.vi

This example will generate a finite number of periods. You can modify the output from the Waveform Generation VI (e.g. concatenate output data - try the Build Waveform VI) in order to get the output required.

The examples mentioned are what I think would make a good starting point. You should go through the others to learn from /combine them to accomplish your goal.

And to answer your original question, the "counter" and "counter-1" are outputs from the task:

taskID of counter is the task ID of the specified counter that generates the pulse train.
taskID of counter -1 is the task ID of the gating counter used to generate the continuous pulse.

You can get more information on a VI by pressing Ctrl + H to bring up the context help, then hover your mouse over the VI.

This VI works with the counter of the device. If you need to generate a sinusoidal signal and a pulse train continusously, you should use the analog output.

I hope this is helpful.

Thanks,
Lesley