Profiler

This functionality is not available in the PLC under Windows CE!

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The "Profiler" function block can be used to allow the execution time of PLC code to be measured. Internally, an instance of the GETCPUACCOUNT function block is called. The measurement is started by a rising edge at the START input, and is stopped by a falling edge. The measurements are evaluated internally, and are then made available for further processing at the DATA output in a structure of type PROFILERSTRUCT. In addition to the current, minimum and maximum execution times, the function block calculates the mean execution time for the last 10 measurements. The number of averaged measured values can be configured via the global variable MAX_AVERAGE_MEASURES between 2 and 100. The times measured are given in microseconds. The output variable DATA.MasureCycle provides information about the number of measurements that have already been carried out. In order to measure the execution time for a specific segment of the PLC program the measurement must be started by a rising edge at the START input when the segment to be measured starts, and stopped by a falling edge at the START input at the end of the segment. All values at the DATA output can be reset if a rising edge is generated at the RESET input at the same time as the rising edge at START. The old measured values are then reset when a new measurement starts and are recalculated from the subsequent calls of the function block.

The times measured can differ from the actual values, since a certain amount of time is needed just for the call of the GETCPUACCOUNT function block. This time depends on the particular computer, and is included in the times that are found.

VAR_INPUT
    START         :BOOL;
    RESET         :BOOL;
END_VAR

VAR_OUTPUT
    BUSY         :BOOL;
    DATA         :PROFILERSTRUCT;
END_VAR

PROGRAM ProfilerTest_ST
VAR
    PROFILER1     :PROFILER;
    ProfilerData  :PROFILERSTRUCT;
    a         :LREAL;
END_VAR

PROGRAM ProfilerTest_FUP
VAR
    Profiler2     :PROFILER;
    Profiler2_Busy    :BOOL;
    Profiler2_Data    :PROFILERSTRUCT;
    b         :LREAL;
END_VAR