Programming instructions

Chapter 11 One-Stop Single-Point Generation
© National Instruments Corporation 11-3 LabVIEW Data Acquisition Basics Manual
Multiple-Immediate Updates
Figure 11-4 shows the block diagram of a VI that performs
multiple updates. The Write N Updates example VI, located in
labview\examples\daq\anlogout\anlogout.llb
, is similar to
Figure 11-4. The diagram shown in Figure 11-4 resembles the one shown
in Figure 11-3, except that the While Loop executes the subVI repeatedly
until either the error status or the stop Boolean is TRUE. You can use the
Easy Analog Output VI, AO Write One Update, in a loop, but this is
inefficient because the Easy I/O VIs configure the device every time they
execute. The AO Write One Update VI configures the device only when the
value of the
iteration
input is set to
0
.
Figure 11-4.
Multiple Immediate Updates Using Intermediate VI
Figure 11-4 shows an immediate, software-timed analog output VI
application. This means that software timing in a loop controls the update
rate. One good reason to use immediate, software-timed output is that your
application calculates or processes output values one at a time; however,
remember that software timing is not as accurate as hardware-timed analog
output. For more information on hardware-timed analog output, refer to
Chapter 12,
Buffering Your Way through Waveform Generation
.