How can I get arbitrary trapezoidal waveform?

[simon_zhang]

I am engaging on a project,need a trapezoidal waveform as standard signal,but there is no this kind of function or example in labview, can any one  help me?

thanks in advance!

Best  regards.

Simon

[devchander]

Hi,

I Had done it once by using ramps.

For my application, i first plotted/generated a rising ramp, next kept a constant output voltage = high of rising ramp, then after an interval, i generated a falling ramp from that high to a specified low.

can u specify the exact shape of the trapezoid you want to generate? we can suggest better

Regards

Dev

[simon_zhang]

HI Dev,

Thanks for your kindly attention!

   Please refer to the attached picture which is standard output pluses train from original spedification of encoder sensor, we have to compare it with actual output signal  which is from our PCBA with the encoder sensor, check output signals difference between them. So  I want to make a standard trapezoidal waveform according to the origianl specification of encoder sensor.

Best regards,

Simon 

[devchander]

Yes my requirement was a similiar waveform

I have a program which will generate a similiar waveform on an Analog output channel of a DAQ card.

Before i send it, can u tell Which hardware are you using??

Message Edited by devchander on 02-13-2006 10:23 PM

[simon_zhang]

Hi Dev,

The hareware is NI PCI 6132  DAQ card,

could you please show me your program, It will be great help for me.

Thanks in advance.

Simon

[devchander]

Hi Simon,

This particular S series card that you are using, does not have analog output channels.

Like i said  before, I used an analog Output channel to generate Trapezoid wave

I am afraid, you cannot generate a Trapezoid wave using any of the DIO's or counters/timers availible on this card

Sorry could not be of more help

regards

Dev

[gitmeb]

Hi Devchander, I'm also trying to generate a trapezoidal waveform, and I'm using an NI 6009 card, which has two analog outputs. Could I possibly take a look at your code?

Thanks a bunch

[devchander]

Hi,

The original VI was for traditional DAQ.

I have modified the VI to work for DAQmx

but right now, i do not have a suitable DAQ card to test it

So, run it and let me know how it works

Regards

Dev

[Sito_1]

devchander,

  Thanks for this bit of code, saved me a some time. Greatly appreciated.

-Wil