PCI6551 back to back waveforms

[dyee]

Is there a way to output two waveforms back to back without a delay inbetween? I have one large waveform that will not fit in memory, and would like to split it up or use the repeat function to shorten portions of it. I seem to get a 400us-600us delay inbetween the end of one waveform and the beginning of the next.

[Allen H]

Hi Dyee,

Using the scripting capability of the 6551, you should be able to achieve what you are asking as long as you can shorten the repetive sections of the waveform. First, take a look at the "Dynamic Generation with Script" example program. You will want to use a single script that steps between multiple waveforms, using the "repeat" statement to generate one piece of a waveform multiple times. For example, the following script will generate waveform A, then repeat the first 50 samples of waveform B 10 times, then finish by generating waveform C:
script MyScript
generate wfmA
repeat 10
generate wfmB subset(0,50)
end repeat
generate wfmC
end script

To find the example program for LabVIEW, go to Help --> Find Examples. Then choos
e Hardware Input and Output --> Modular Instruments --> NI-HSDIO --> Dynamic Generation --> Scripted. For C or CVI, go to C:\Program Files\IVI\Drivers\niHSDIO\Examples