Measuring pulses riding on dc voltage.

[slash]

Hello, I have a question regarding measuring triggered pulses using labwindows cvi. I have a TTL pulse riding on a 1Vdc. I am able to measure the TTL pulse using labwindow's triggered pulse library function. how can I verify the 1vdc voltage that the pulse is riding on? can somebody please help me out.
Thanks

[imanon]

Well, I guess it would depend on what you mean by "verify" but a simple way of looking at the data & seeing if the dc offset is visible is to use the CVI PlotWaveform() call in conjunction w/ a graph control.  Have you tried that already?

Regards,

Andy

[slash]

Thanks for the reply Andy,

Yes I was able to display the waveform using niScope call in functions.( I am using NI 5112 scope card 8-bit digitizer 100MHZ 100MS/s). I also have a SCB-68 pin shielded connector Block with a AT-MIO-16E board. I was able to capture a triggered pulse of the waveform using AIAcquireTriggeredWaveforms() function. I was also able to save the samples into a  *.txt file. I can clearly see the 1V dc value in the record. This is the part I need some advice. Would it be valid if I write a simple program to isolate the samples with 1Vdc and take an average(mean) value to justify the 1Vdc voltage of the waveform? 

Thank you in advance

CB

[imanon]

Sounds reasonable to me, slash, but maybe some of the more experienced test engineers who frequent this site have other suggestions.  One thing I was wondering about was why you don’t subtract out the 1v offset from your result & plot the fundamental signal to see if it matches the characteristics of a TTL compatible signal in terms of high & low signal levels, rise & fall times, minimum pulse width, etc.  If so, then wouldn’t that be the validation you are seeking?  Then again, maybe I am misunderstanding your problem.....

Regards,

Andy