Serial Decode/Lister 10
InfiniiVision Oscilloscopes User’s Guide 299
• Data length code (DLC) appears in blue for data frames and green for remote frames.
• Data bytes appear in hex digits in white for data frames.
• Cyclic redundancy check (CRC) appears in hex digits in blue when valid, or in red to
indicate that the oscilloscope’s hardware decode calculated a CRC that is different
from the incoming CRC data stream.
• Angled waveforms show an active bus (inside a packet/frame).
• Mid-level blue lines show an idle bus.
• Decoded text is truncated at the end of the associated frame when there is insufficient
space within frame boundaries.
• Red dots in the decode line indicate that there is data that is not being displayed.
Scroll or expand the horizontal scale to view the information.
• Aliased bus values (undersampled or indeterminate) are drawn in red.
• 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.
To Next Page
Loading...
Need help?
General
