AnsweredAssumed Answered

Agilent 16901A - MATLAB R2012a DCOM Speed

Question asked by dprl001 on Oct 1, 2012
Latest reply on Oct 2, 2012 by algoss
Hello, I am having a hard time understanding why things are taking so long over distributed com and was hoping this forum could help guide me to a faster solution.

The goal is to pull data from the logic analyzer into MATLAB running on a separate computer. I've been able to do this, but I'm very surprised at how long it is taking. Pseudocode for the data collection script:

LA.h_Inst.Run;
LA.h_Inst.WaitComplete(5);

GetDataBySample(all)   %% this takes almost 5.8s for (4M Capture)
GetDataBySample(all)   %% 0.8s
GetDataBySample(all)   %% 0.8s
GetDataBySample(all)   %% 0.8s

A timing analysis showed that the first call to GetDataBySample took almost 5.8 seconds (4M capture). The subsequent calls each took under 1 second (0.85s on average). Why is there such a slowdown for the first GetDataBySample call? Can this be avoided?

The first two lines (Run, WaitComplete) also take on average around 3 seconds to execute, when on the actual logic analyzer, the data capture is nearly instantaneous after hitting the run button (capturing from an ADC with I think a 100 MHz clock). Is there a reason these operations take so long as well?

I hope I am doing something wrong in the MATLAB interface and these speeds aren't typical. Thanks for the help!  

Outcomes