User manual

Protocol Analysis
R&S
®
RTO
292User Manual 1316.0827.02 ─ 06
"Data max"
The second data pattern is required to specify a range with conditions
"In range" and "Out of range".
SCPI command:
TRIGger<m>:CAN:BORDer on page 691
TRIGger<m>:CAN:DCONdition on page 690
TRIGger<m>:CAN:DMIN on page 691
TRIGger<m>:CAN:DMAX on page 691
TRIGger<m>:CAN:DLCCondition on page 692
TRIGger<m>:CAN:DLC on page 692
Error conditions: CRC, Bit stuffing, Form, Ack
If a CAN detects a bit stuffing error, form error, or ack error, it transmits an error flag at
the next bit. The R&S RTO detects errors in the message and triggers on these errors
even if no CAN node sends an error flag.
●
CRC error
CAN uses the Cyclic Redundancy Check, which is a complex checksum calculation
method. The transmitter calculates the CRC and sends the result in the CRC
sequence. The receiver calculates the CRC in the same way. A CRC error occurs
when the calculated result differs from the received value in the CRC sequence.
●
Bit stuffing error
The frame segments Start Of Frame, Arbitration Field, Control Field, Data Field and
CRC Sequence are coded by the bit stuffing method. The transmitter automatically
inserts a complementary bit into the bit stream when it detects five consecutive bits
of identical value in the bit stream to be transmitted. A stuff error occurs when the 6th
consecutive equal bit level in the mentioned fields is detected.
●
Form error
A form error occurs when a fixed-form bit field contains one or more illegal bits.
●
Ack error
An acknowledgement error occurs when the transmitter does not receive an acknowl-
edgment - a dominant bit during the Ack Slot.
SCPI command:
TRIGger<m>:CAN:CRCerror on page 693
TRIGger<m>:CAN:BITSterror on page 693
TRIGger<m>:CAN:FORMerror on page 693
TRIGger<m>:CAN:ACKerror on page 692
10.5.1.3 CAN Decode Results
To display the decoded signal below the waveforms, enable "Decode" on the "Configu-
ration" tab.
Additionally, you can display the binary signal and the detailed decoding results using
the setting on the "Display" tab, see chapter 10.1.2, "Display", on page 251.
Data is decoded and displayed in the order of its reception. The endianess setting is not
considered for decoding. The "Decode results" box shows the detailed decoded data for
each frame as it is received.
CAN (Option R&S RTO-K3)