2-11
IM 701450-51E
CAN Bus Signal Analysis Function
2
Setting the Trigger Level, Trigger Coupling, Etc.
32.
Press the
Level/Coupling
soft key. The Level/Coupling dialog box opens.
33.
Set the trigger level, trigger hysteresis, trigger coupling, and HF rejection of
each channel. For the setup procedure, see steps 9 to 14 on page 6-16 in the
DL7440/DL7480 User’s Manual (IM701450-01E)
.
34.
Press
ESC
. The Level/Coupling dialog box closes.
Setting the Trigger Mode
35.
Set the trigger mode according to the procedures given in section 6.1, “Setting
the Trigger Mode” in the
DL7440/DL7480 User’s Manual (IM701450-01E)
.
Setting the Record Length
36.
Set the record length according to the procedures given in section 7.2, “Setting
the Record Length” in the
DL7440/DL7480 User’s Manual (IM701450-01E)
.
Starting/Stopping the CAN Bus Signal Acquisition
37.
Press
START/STOP
to start the CAN Bus signal acquisition. Triggers are
activated on the specified trigger conditions.
To proceed to the analysis, press
START/STOP
to stop the CAN Bus signal
acquisition.
Explanation
Setting the Trigger Conditions of the CAN Bus Signal: CAN Setup
You can set the following conditions.
Bit Rate
Select a data transfer rate for the CAN Bus data to be analyzed from the following.
10, 20, 33.333, 50, 62.5, 83.333, 95.238, 100, 125, 250, 500, or 1000 [kbps]
You can also enter an arbitrary value* from the keyboard that appears on screen.
Selectable range:
10.000 to 1000.000 [kbps]
Resolution:
Bit time (reciprocal of the bit rate) resolution of 0.5
µ
s
*
If you enter an arbitrary value using the numeric keys, the value that is actually entered may
differ from the value you specified. This is because, the bit rate resolution on the instrument
is set to the bit time (reciprocal of the bit rate) resolution of 0.5 [
µ
s], and the instrument
rounds the entered bit rate to the bit rate closest to the bit time conversion.
For example, if you input a bit rate of 450 [kbps] using numeric keys, the actual bit rate that is
entered is 500 [kbps]. The bit time when the bit rate is set 450 [kbps] is 2.22 [
µ
s]. However,
because the resolution is 0.5 [
µ
s], the bit time is rounded to 2.0 [
µ
s] which corresponds to a
bit rate of 500 [kbps]. If you input a bit rate that would cause the bit time to fall in the middle
of the resolution (such as 800 [kbps] which corresponds to a bit time of 1.25 [
µ
s]), the bit rate
is set a rate that corresponds to a longer bit time (in this case, 666.667 [kbps] because 1.5
[
µ
s] is longer than 1.0 [
µ
s]).
2.4 Setting CAN Bus Signal Acquisition Conditions