How to continously generate a voltage signal with dynamic amplitude.

Hello all,
I am looking for ideas and pointers (help in other words). I would like to generate a voltage signal (sine for example) on a AO of my NI cRIO-9263 (DAQmx). The signal should be:
continuous (without jumps ie. smooth)
dynamically able to be change the amplitude, frequency and sampling rate.
interuptable so that the AO can be turned off.
I have tried to use the DAQ Assistant but once it runs in continous mode, I have the impression that the waveform should not be changed. Is there maybe a way where I send repeatedly N samples of the waveform to the AO and gain more control over the signal that way. But if I do that how can I ensure that the signal is continous?
Further more this output has to be generated in an event application ie. in the background.
Your ideas and input is appreciated. Thanks, Bernie

See if this example VI helps
Ches this one too

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How to continuously generate a pulse train with variable frequency

Dear all,
I am trying to use NI-USB 6259(BNC) to send Pulse signals to conduct position control of a servo motor with labview. The position control of servo motor follows these rules:
The number of the pulse train determines how many degrees the motor rotate ;( e.g. the angular position of motor)
The frequency of pulses determines how fast the motor rotate; (e.g. the speed of motor rotating)
The digital determines the direction of rotation of motor (e.g. clockwise or counterclockwise)
My question comes when I need to continuously generate a finite plus train signal in a period of time. Below is a sample:
Time(s)
Number of pulses
Direction of rotation
(1 is clockwise, 0 is counterclockwise)
Frequency
0-1
923
1
923hz
1-2
3540
0
3540hz
2-3
1751
1
1751hz
3-4
2663
0
2663hz
4-5
353
0
353hz
5-6
1017
1
1017hz
6-7
3436
1
3436hz
7-8
302
0
302hz
8-9
1513
1
1513hz
9-10
570
1
570hz
Here is the explanation of this table, the motor keeps rotating in clockwise direction during 0~1s. When the time reaches 1s, the motor just complete the rotation of 923 pulse signals. And then the motor starts to rotate in counterclockwise direction during 1s~2s. When the time reaches 2s, the motor just complete the rotation of 3540 pulse signals. So we can see that the rotating speed of motor in 0~1s is different from the speed in 1s~2s. Namely, the frequency of pulse signal in 0~1s is different from the frequency in 1s~2s.
I have already use the counter output of DAQmx, it just can generate pulse signal with certain numbers and certain frequency in one time. The attachment is the vi which can generate a finite digital pulse train from a counter output channel and the frequency, duty cycle, Initial delay, and Idle state are all configurable.
How can I continuously generate a series of pulse train with varying numbers and frequencies during a certain period of time.
Thank you very much for your help!
Solved!
Go to Solution.
Attachments:
Counter - Finite Output.vi ‏57 KB
Finite output.png ‏13 KB

Hi aacuna,
Thank you for your reply!
I already checked that article. The frequency in that Vi can change dynamically, but the method of adjusting the frequency is ‘manual’ .Below is the front panel of that Vi. When the Vi is running we can change the frequency by press the button.
Time(s)
Frequency
0-1
923hz
1-2
3540hz
2-3
1751hz
3-4
2663hz
4-5
353hz
5-6
1017hz
6-7
3436hz
7-8
302hz
8-9
1513hz
9-10
570hz
Thank you！

How can we generate a pulse train with variable inster pulse delays?

I want to generate a pulse train with random inter pulse delays (100us-10000us) and the pulse width would be 50-100us. I programmed for single pulse generation using counter cfg,a for loop contaning set attribute parameters pulse spec 1 and pulse spec 2. I changed the pulse spec 1 value in every cycle
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I want to make voltage aquisition with a PXI 6713 card. I take the Channels ai16 to ai33. The voltage at the clamp is 3.886VDC ( measured with a DMM ). When i measure the voltage and calculate it into a current ( see my applikation atteched ) the result is something between -10 and -24mA?!?!?
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RSE
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I hope of yous Answer.
Thanks
Attachments:
analog_voltage_aquisition.jpg ‏33 KB

Is it a trick question??
First of all, Looks like you mentioned the card wrong PXI 6713 is an AO card, without any AI channels
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Hello,
I have a question.
I have a PXI-6115 and some other card in my mainframe.
These other cards nee 10 Mhz pulses on line PXI-Star1 and 2.5 MHz on PXI_trg7.
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Thanks for replying!
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How to continously generate a voltage signal with dynamic amplitude.

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