National Instruments NI-FBUS - Manual (Page 47)

Chapter 2 Using the NI-FBUS Configurator
NI-FBUS Configurator User Manual 2-24 ni.com
6. Set the sample Interval of the trend in loops/sample. The interval
should be a multiple of any loop macrocycle time in which this block
is involved. For example, if the interval is 2 loops/sample, and the loop
macrocycle time is 1 s, the trend will acquire a value every 2 s.
7. Set the Sample Type. Select Instant or Average from the Sample
Type drop-down list. Instant trends the actual value. Average trends
all samples.
Note If you want to view trends on a host computer, that computer must have software.
The NI-FBUS Configurator does not have trend-viewing functionality.
View and Edit a Schedule
The NI-FBUS Configurator automatically determines the execution order
and timing of the schedule based on your control strategy, network and
device factors, and the loop execution rate you choose. The NI-FBUS
Configurator also automatically optimizes the schedule.
The Link Active Scheduler (LAS) is a device that dictates both scheduled
and unscheduled communication according to the schedule downloaded to
it. The Primary LAS field on the schedule window displays the name of
the device that is the primary LAS for the system.
Change the Link Active Schedule
You can change the schedule by completing the following steps:
1. Double-click the Schedule icon in the configuration tree.
The schedule window appears.
2. Click the Scale field to display or change the time and divisions on the
timing diagram.
3. Use the cursor to drag the function blocks in the schedule as desired.
Dragging bars in the schedule shuts off the automatic optimization.
If you want to reoptimize, click the Optimize Schedule button on the
schedule window toolbar.
4. During the time between scheduled and unscheduled communications,
the LAS allows unscheduled communications to occur. Unscheduled
communications are always secondary to scheduled communications.
The ratio of scheduled to unscheduled time can have an affect on data
throughput rates.
5. To verify the schedule, click the Errors button in the schedule window.