Datasheet

www.tektronix.com/oscilloscopes 23
Debugging Serial Buses in Embedded System Designs
Now imagine performing this task without these capabilities.
Without the CAN triggering you would have to trigger on the
switch itself, capture what you hope is a long enough time
window of activity and then begin manually decoding frame
after frame after frame on the CAN bus until you finally find
the right one. What could have taken tens of minutes or hours
before can now be accomplished in moments.
The oscilloscope's powerful CAN triggering capability includes
the following types:
Start of Frame – trigger on the SOF field.
Frame Type – choices are Data Frame, Remote Frame,
Error Frame, and Overload Frame.
Identifier – trigger on specific 11 or 29 bit identifier values
with Read / Write qualification.
Data – trigger on 1-8 bytes of user specified data. Missing
Ack – trigger anytime the receiving device does not provide
an acknowledge.
End of Frame – trigger on the EOF field.
These trigger types enable you to isolate virtually anything
you’re looking for on a CAN bus effortlessly. Triggering is
just the beginning though. Troubleshooting will often require
inspecting message content both before and after the
trigger event. A simple way to view the contents of multiple
messages in an acquisition is with the Event Table, as shown
in Figure 32.
The event table shows decoded message content for every
message in an acquisition in a tabular format with timestamps.
This makes it easy to not only view all the traffic on the
bus but also enables easy timing measurements between
messages. Event Tables are available for all types of buses the
oscilloscope supports.
Figure 32. CAN event table.