Agilent Technologies InfiniiVision 3000 3024A MSO-X, User Manual

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CAN/LIN Triggering and Serial Decode
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Agilent InfiniiVision 3000 X-Series Oscilloscopes User's Guide 341
• Aliased bus values (undersampled or indeterminate) are drawn in pink.
• Unknown bus values (undefined or error conditions) are drawn in red
with a "?" label.
• Flagged error frames are drawn in red with an "ERR" label.
CAN Totalizer
The CAN totalizer provides a direct measure of bus quality and efficiency.
The CAN totalizer measures total CAN frames, flagged error frames,
overload frames, and bus utilization.
The totalizer is always running (counting frames and calculating
percentages) and is displayed whenever CAN decode is displayed. The
totalizer counts even when the oscilloscope is stopped (not acquiring
data). Pressing the
[Run/Stop] key does not affect the totalizer. When an
overflow condition occurs, the counter displays OVERFLOW . The counters
can be reset to zero by pressing the
Reset CAN Counters
softkey.
Types of Frames
• Active error frames are CAN frames in which a CAN node recognizes
an error condition during a data or remote frame and issues an active
error flag.
• A partial frame occurs when the oscilloscope detects any error
condition during a frame that is not followed by an active error flag.
Partial frames are not counted.
Counters
• The FRAMES counter gives the total number of completed remote, data,
overload, and active error frames.
• The OVLD counter gives the total number of completed overload frames
and their percentage of the total number of frames.
• The ERR counter gives the total number of completed active error
frames and their percentage of the total number of frames.
• The UTIL (bus load) indicator measures the percentage of time the bus
is active. The calculation is done on 330 ms periods, approximately
every 400 ms.