User manual

Protocol Analysis
R&S
®
RTO
287User Manual 1316.0827.02 ─ 06
If you measure with a differential probe, connect the probe to both CAN-H and CAN-L
lines, and select the data "Type" CAN-H.
With single-ended probes, connect the probe to either CAN_L or CAN_H, and select the
data type accordingly.
SCPI command:
BUS<m>:CAN:TYPE on page 685
Threshold
Sets the threshold value for digitization of the signal. If the signal value on the line is
higher than the threshold, the signal state is high (1 or true for the boolean logic). Oth-
erwise, the signal state is considered low (0 or false).
There are three ways to set the threshold:
"Threshold"
Enter the value directly in the field.
"Set to 50%"
Executes the measurement of reference levels and sets the thresholds to the middle
reference level of the measured amplitude.
"Preset"
Selects the default threshold voltage for various signal technologies from a list. The
value is set to "Manual" if the threshold was set with "Set to 50%", or was entered
directly.
SCPI command:
BUS<m>:CAN:DATA:THReshold on page 685
BUS<m>:CAN:TECHnology on page 685
Bit rate
Sets the number of transmitted bits per second. The maximum bit rate for High Speed
CAN is 1 Mbit/s. The bit rate is uniform and fixed for a given CAN bus.
To select a bit rate from the list of predefined values, tap the icon beside the "Bit rate"
field. To enter a specific value, open the keypad. The list of predefined values is also
available in the keypad.
SCPI command:
BUS<m>:CAN:BITRate on page 686
Synchronization: Sample point, Time segments, Jump width
The CAN bus interface uses an asynchronous transmission scheme. The standard
specifies a set of rules to resynchronize the local clock of a CAN node to the message.
In R&S RTO, tha sample point divides the nominal bit period into two distinct time seg-
ments. The length of the time segments is defined in time quanta according to network
and node conditions during CAN development.
CAN (Option R&S
RTO-K3)