Baud rate
Auto-Baud-Rate
In order for automatic baud rate detection to function, it is necessary for a number of valid telegrams to be present on the bus at the desired baud rate. The RUN and CAN ERR LEDs blink in rapid alternation while the baud rate search is in progress. Once a baud rate was detected and accepted, the Bus Terminal Controller continues with the initialization.
A software reset does not lead to a new baud rate search. The previously active baud rate is maintained.
Bit Timing
The following baud rates and entries in the bit-timing register are supported by the BECKHOFF CANopen devices:
|
Baud rate [kbaud] |
BTR0 |
BTR1 |
Sampling Point |
|---|---|---|---|
|
1000 |
0x00 |
0x14 |
75% |
|
800 |
0x00 |
0x16 |
80% |
|
500 |
0x00 |
0x1C |
87% |
|
250 |
0x01 |
0x1C |
87% |
|
125 |
0x03 |
0x1C |
87% |
|
100 |
0x04 |
0x1C |
87% |
|
50 |
0x09 |
0x1C |
87% |
|
20 |
0x18 |
0x1C |
87% |
|
10 |
0x31 |
0x1C |
87% |
The bit-timing register settings given (BTR0, BTR1) apply, e.g. for the Philips 82C200, SJA1000, Intel 80C527, Siemens 80C167 and other CAN controllers. They are optimized for the maximum bus length.