Agilent Technologies HP 1660E Series User Manual page 384

System Performance Analysis (SPA) Software
System Performance Analysis Software
Running the acquisition again, you discover that the interrupt usually
takes the expected 8 microseconds, but occasionally it takes as long as
8milliseconds. After experimenting with the target system while
monitoring the interrupt with Time Interval mode, a faulty key on the
keyboard is discovered. The key is bouncing excessively, resulting in an
extended interrupt routine call.
The figure below shows the Time Interval display for this example.
SPA Time Interval
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