03 | Keysight | Serial Bus Options for InfiniiVision X-Series Oscilloscopes - Data Sheet
Hardware-Based Decoding
Automatic Search and Navigation
Figure 1. Hardware-based decoding quickly reveals serial communication
errors.
Figure 3. Automatic “Search &
Navigation” quickly finds user-
specified serial bus frames/bytes of
interest.
Keysight’s InfiniiVision Series oscilloscopes are the industry’s only
Keysight’s InfiniiVision Series oscilloscopes are the industry’s only
scopes to use hardware-based decoding. Most other vendor’s
scopes with serial bus triggering and protocol decode, use
software post-processing techniques to decode serial packets/
frames. With these software techniques, waveform- and decode-
update rates tend to be slow (sometimes seconds per update.)
That’s especially true when using deep memory, which is often
required to capture multiple packetized serial bus signals. And
when analyzing multiple serial buses simultaneously, software
techniques can make decode update rates even slower.
After capturing a long record of serial bus communication using
the InfiniiVision scope’s MegaZoom deep memory, you can
easily perform a search operation based on specific criteria
that you enter. Then, you can quickly navigate to bytes/frames
of serial data that satisfy the entered search criteria. Figure 3
shows an example of searching on captured I2C data to find all
occurrences of Read or Write operations with “No Ack.” In this
case, the scope found five occurrences of data transfers with “No
Ack,” and marked each occurrence with a white triangle to show
where in time they happened relative to the captured waveform.
Navigating and zooming-in on each marked byte/frame is quick
and easy using the scope’s front panel navigation keys. Search
and Navigation not available for DSOXT3CXPI/DSOX4CXPI.
Faster decoding with hardware-based technology enhances
scope usability, and more importantly, the probability of
capturing infrequent serial communication errors. Figure 1 shows
an example of a Keysight InfiniiVision X-Series scope capturing
a random and infrequent CAN error frame. The upper half of the
scope’s display shows the decoded data in a “Lister” format,
along with a time-correlated decode trace shown below the
waveform.
Symbolic Trigger and Decode
With the DSOXT3AUTO, DSOX4AUTO or DSOX6AUTO option
licensed on a 3000T, 4000 or 6000 X-Series oscilloscope, you
can import a .dbc file that defines your multi-node CAN network.
The oscilloscope can then trigger on and decode the CAN bus
symbolically as shown in Figure 2. LIN symbolic trigger and
decode is also supported on the 3000T, 4000, and 6000 X-Series
oscilloscopes by importing an industry-standard .ldf file.
Figure 2. Symbolically decoding the CAN bus.
KEYSIGHT [ Keysight Technologies ]
