Agilent Technologies 1670E Series, User Manual

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System Performance Analysis (SPA) Software
System Performance Analysis Software
SPA measurement processes
This section introduces you to the measurement processes of the
System Performance Analysis (SPA) software. It tells you how to select
the appropriate trace mode and labels. It also explains how SPA
samples and sorts data.
Selecting and changing trace modes
SPA has three trace modes: State Overview, State Histogram, and Time
Interval. These are selected by the Trace Mode field in the SPA data
display.
Only the currently displayed trace mode is affected during an
acquisition. While acquiring and viewing data in one trace mode, the
other two trace modes are not updated. If the trace mode or any other
critical variable is changed during an acquisition, the logic analyzer
stops the acquisition and displays "Warning: Run HALTED due to
variable change."
Each trace mode only performs statistics on its own database.
Therefore, if acquisitions are completed in two different trace modes,
the two modes will not contain the same data.
For example, you select the State Overview mode and press the Run
key. After the data accumulates for a period, press Stop. You then
select the Time Interval mode and the screen is blank since no data has
been acquired in this mode. You again press Run, and let data
accumulate and press Stop. In this example, two separate data sets are
acquired, the first for State Overview mode, the second for Time
Interval. You can now move between the modes and see the correct
data for the associated measurement.
This separate acquisition data applies to all three trace modes. In this
way, three separate views of the target system can be acquired and
stored in SPA.