Exercise 5a: Timing and pulse generation In this exercise we will work with the onboard timers of the NI 6221 DAQ card. We wil use the programs Timer.cpp and Pulse_Train.cpp given in Introduction to DAQmx Data Acquisition Programming of Appendix VI, available in the AEP2640 folder in your computer. Time interval measurement Run the program Timer.cpp and observe the minimum measurable time delay between two DAQmxReadCounterScalarU32() function calls. Now record the displayed time intervals when the delay function is used to set desired time intervals of 10, 20, 50, 100, 200, 500 and 1000 milliseconds. What conclusion can you draw concerning the computer “overhead” associated with the delay() function? This is the reason that a time interval of 200 milliseconds was used in the DAC example of Exercise 3. Time delays less than 200 milliseconds will need to be corrected for the additional execution time for the delay() function. Continuous pulse generation
This is the end of the preview. Sign up
access the rest of the document.
This note was uploaded on 10/20/2009 for the course AEP 2640 at Cornell.