Example 4 - Calculate An Fst's Approximate Execution Rate - Emerson Micro Motion 3711 Configuration And Use Manual

Function Sequence Tables
11.9.4 Example 4 – Calculate an FST's approximate execution rate
This portion of an FST determines the average time it takes to execute the FST. A timer is used to
determine the number of 100-millisecond intervals that have elapsed while a sequence of functions
executes. It is important to note that the operating system can perform the FST execution at the same
time as other tasks.
The FST is shown in Figure 11-9. In this FST:
• Step 0: Set Timer 1 to 100 100-millisecond intervals (10 seconds).
• Steps 1–4: Any FST functions.
• Step 5: Store the value in Timer 1 to RR.
• Step 6: Write the value in RR to R6.
• Steps 7–11: The FST sequence for which execution rate is being calculated.
• Step 12: Store the value in Timer 1 to RR.
• Step 13: Write the value in RR to R7.
You can now subtract R6 from R7 and multiply the result by 0.1. The final value will be the execution
rate in seconds, rounded to the nearest tenth of a second.
Figure 11-9 FST Example 4
Configuration and Use Manual
FST body
FST body
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