Technical data

Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs 4
4000 X-Series Oscilloscopes Advanced Training Guide 113
Your scope should now be triggering on LIN frame = 21
HEX
as shown in
Figure 75. With this scope’s very fast hardware- based decoding, you
should also see that the frame ID field (left- most decoded byte) is
sometimes displayed in red. This is an indication that the scope is
capturing and quickly decoding infrequent parity bit errors. If the scope
detects a checksum error, the last byte in the serial string (checksum byte)
will be displayed in red. Note that Frame ID = 12
HEX
contains an
occasional checksum error. If you change to the trigger condition to trigger
on ID = 0x12, you can observe this particular type of error. Let’s now
capture a very long stream of LIN traffic (2 seconds of acquisition time)
and then manually search through the captured and decoded record.
16 Press the [Serial] front panel key.
17 Tap the Lister softkey; then select Half-Screen from the Window menu.
18 Set the scope’s timebase to 200.00 ms/div.
19 Press [Run/Stop] to stop repetitive acquisitions.
20 Tap the Scroll Lister softkey; then turn the Entry knob to manually scroll
through the lister table.
Figure 75 While triggering on LIN frame = 21
HEX
, the scope’s hardware-based decoding
reveals parity bit errors in the frame ID field.