HP 1660CS-Series User Manual page 236

System Performance Analysis (SPA) Software
SPA measurement processes
Time Interval mode
Time Interval mode shows distribution of execution time of a single event.
The event is defined by specifying Start and End conditions as patterns
across all labels defined in the Format Specification.
Data sampling and sorting When you press Run, the analyzer samples
the target system using the definitions entered in the Format
Specification. During acquisition, the state analyzer searches the data
for the start and end conditions, and uses the analyzer's time tag feature
to time the event. The time durations for each Start/End pair are then
sorted into user-definable time interval ranges on the display. The
acquisition is repeated until Stop is pressed or until a display variable is
changed.
Because time tags are not available in the half-channel mode as specified in
the Format menu, time interval mode will not function when half-channel
mode is selected.
After the data is sampled, timed, and sorted, the histogram for each time
interval range is updated.
If two time intervals are adjacent and have a common boundary (the upper
limit of one equals the lower limit of the next), and a sampled time interval
falls on the common boundary, the sample will be sorted into the higher time
interval.
Start/End conditions Start and end conditions for Time Interval are
specified on all labels defined in the Format Specification as a
combination of values, in the current base, and don't cares.
If a start or end condition is not found during an acquisition, the histogram
will not change. The analyzer will only update when a start and stop event
are both found.
Start and end conditions need not be adjacent in the data stream. For
example, when the state analyzer sees the specified start condition, it starts
the timer. If the start condition occurs again before the end condition occurs,
the timer will not be reset.
For measurement purposes, the analyzer measures the time between the first
occurrence of the start condition and the first occurrence of the stop
condition.
Time Interval ranges Up to 8 time interval ranges are available. Each
range has a lower and upper limit which can be entered manually. The
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