ESD electronic CAN-CBM-PLC/331-1, Hardware Manual

Page: 122 / 149

Commands and Parameters
esd Protocol for CAN Modules Rev. 3.2 3 - 11
If no communication is possible with the module, this is often due to a wrong
adjustment of the bitrate.
If the local software discovers a malfunction on the CAN, the bitrate is adjusted
again to the default value (adjustment at the configuration jumper of the module),
but without changing the other parameters.
The specified typical line lengths base on experimental values from experience. The
minimum reachable line lengths result from the 'worst case' delay times of the used
components.
baud
[hex]
CAN controller
register
Bit rate
[kBit/s]
Typical values of
the reachable line
length l
max
[m]
Minimum values
of the reachable
line length l
min
[m]
BTR0
[HEX]
BTR1
[HEX]
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
00
00
00
00
01
01
02
03
04
45
09
4B
18
5F
31
14
16
18
1C
18
1C
1C
1C
1C
2F
1C
2F
1C
2F
1C
1000
800
666.6
500
333.3
250
166
125
100
66.6
50
33.3
20
12.5
10
37
59
80
130
180
270
420
570
710
1000
1400
2000
3600
5400
7300
20
42
65
110
160
250
400
550
700
980
1400
2000
3600
5400
7300
The specifications in the table base on the limit values of the bit timing of the
CAN protocol, the runtime of the local CAN interface and the runtime of
the cable. The runtime of the cable is assumed with about 5.5 ns/m. Further
influences, e.g., by the terminal resistances, the specific resistance, the
geometry of the cable of outer interference effects at the transmission have
not been included in the specifications!
Table 3.2.3:
Allocation of the bitrate to the registers of the controller SJA1000