Baud Rate
The baud rate does not have to be set for the fieldbus box. These modules include an automatic baud rate function.
Via table 100 a fix baud rate can be set (see below).
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 flash in rapid alternation while the baud rate search is in progress. As soon as a baud rate has been detected and adopted, the Fieldbus Box begins initialization.
A software reset does not cause the automatic baud rate function to be activated again - the baud rate that was previously active is retained.
Bit Timing
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, for example, for the Philips 82C200, SJA1000, Intel 80C527, Siemens 80C167 and other CAN controllers. They are optimized for the maximum bus length.
Fix baud rate setting
Via KS2000 Configuration Software you can change the settings of the CANopen module. This is possible from firmware version C6. The present firmware version of your module is displayed by KS2000 Configuration Software.
Note To use this settings you have to disable the register write protection via KS2000 Configuration Software bevore. |
Meaning of the entries in table 100
|
Table100, Offset |
Description |
Default |
|---|---|---|
|
000 |
Baud rate to be set fix |
0 (see table) |
|
001 |
reserved |
reserved |
|
002 |
reserved |
reserved |
|
003 |
reserved |
reserved |
|
004 |
reserved |
reserved |
|
005 |
Auto baud active |
0 |
|
006 |
reserved |
reserved |
|
007 |
reserved |
reserved |
|
008 |
reserved |
reserved |
|
009 |
reserved |
reserved |
|
010 |
Activation of a fix baud rate |
0 |
|
011-018 |
reserved |
reserved |
Example of setting a fix baud rate
A fix baud rate can be stored to register 0 of table 100. This setting can be activated in register 10.
Example for 50 kBaud:
- Deactivate the write protection
- Open table 100
- Write 0x0007 to offset 0 (see table of supported baud rates)
- Write 0x8000 to offset 10
- Write 0x0001 to offset 5
- Restart the module
A fix baud rate of 50 kBaud is set now!
|
Value in table 100, offset 0 |
baud rate |
|---|---|
|
0x0000 |
1 MBaud/Auto |
|
0x0001 |
800 kBaud |
|
0x0002 |
500 kBaud |
|
0x0003 |
400 kBaud |
|
0x0004 |
250 kBaud |
|
0x0005 |
125 kBaud |
|
0x0006 |
100 kBaud |
|
0x0007 |
50 kBaud |
|
0x0008 |
20 kBaud |
|
0x0009 |
10 kBaud |