Help with external trigger to analog output

[name444]

Hello,

I have the USB-6341 board and NI-DAQmx driver. 

I hope someone can give me an example about what I am trying to do using C#.

I want to increase one of the analog output from -10V up to +10V in such a way that each time the board receives external trigger it will increase the analog voltage 100mV. And after M times(when the output voltage becomes 10V) analog output again should go back to -10V. I would be very glad.

Can someone show me an implementation of this?

Kind regards

[santo_13]

I can give you an idea instead of implementation.

1. Use the external trigger signal as a sample clock and use rising edge
2. Load an array of values -10V to +10V at 100mV steps to AO. Wire the array size as the samples per channel count.
3. Start the task
4. Every time DAQ gets trigger edge, it will auto iterate to the next sample in the array.
5. Once it reaches the +10V element of the array, next time it will wrap back to -10V due to the default regenerate property of DAQmx task

[name444]

Thank you for the procedure. I guess you use  LabView. Maybe someone else show how to implement it in C# syntax. Thanks

[name444]

Hello again,

Can this be done with USB-6003 as well

https://www.ni.com/da-dk/support/model.usb-6003.html

[santo_13]

Unfortunately, you CANNOT use an external signal as a timebase/sample clock for USB-6003

[name444]

Thank you. I will go for 6341 then. You described a procedure for the original question and I need to increase one of the analog output in staircase way where for each external trigger rising edge from an external clock source(20kHz) cause analog output to increase 20mV.

So I saw two examples in under NI-DAQ\Examples\DotNET4.5\Analog Out\

One of them is: ContGenVoltageWfm_ExtClk

The other one: ContGenVoltageWfm_ExtClkDigStart

Which one should I use do you think? And those examples using sine wave as output. In my case I need DC analog output at each step.

Do you have any idea about it? 

[santo_13]

ContGenVoltageWfm_ExtClk would be the right example and replace the sine wave array with your ramp waveform array.

Wire your external trigger/clock to one of the PFI ports and select that PFI port as the Clock source in the UI/program.