Appendix D Baud Rate Configuration Via Unit Settings - Omron C200HW-CORT21-V1 Operation Manual

Baud rate configuration via Unit settings
The standard CANopen baud rates are selectable via the DIP-switches at the front of the Unit (see section
3-1-4). However, if a different baud rate is required, it is possible to configure this via the Unit settings. The
Unit settings only overrule the DIP-switch settings when all the configured values are within the specified
ranges. By default, these Unit settings are zero and therefore the DIP-switches determine the baud rate.
The Unit settings are made in a dedicated DM area. Refer to section 4-2-3 for the relationship between the
Machine Number and the location of the dedicated DM area.
The DM settings directly configure the hardware registers of the CAN interface that determine the baud rate.
Incorrect settings will cause improper functioning of the CAN interface. Users with little CAN experience are
advised to contact their distributor to assist in setting the correct values.
The table below lists the DM words for configuration of the baud rate.
DM word Value
m+16 0000 ~ 0063
m+17 0000 ~ 0003
m+18 0002 ~ 0015
m+19 0001 ~ 0007
Baud rate =
Recommended:
The following table lists the values of BRP, SJW, TSEG1, and TSEG2 for the standard CANopen baud rates
that can be selected with the DIP-switches.
Baud rate (kbit/s)
10
20
50
125
250
500
800
1000
Appendix D
Meaning
BRP value
The Baud Rate Prescaler value determines the length of the time quanta
within one bit time.
SJW value
The (Re)Synchronisation Jump Width defines the maximum number of time
quanta a bit time may be shortened or lengthened by one resynchronisation.
TSEG1 value
TSEG1 is the time segment within a bit time before the sample point.
TSEG2 value
TSEG2 is the time segment within a bit time after the sample point.
8 000
(BRP + 1) x (3 + TSEG1 + TSEG2)
TSEG2 ≥ SJW
TSEG1 > TSEG2
TSEG1 + TSEG2 ≥ 5
BRP
0049
0024
0009
0003
0001
0000
0000
0000
[kbit/s]
SJW TSEG1
0000 0012
0000 0012
0000 0012
0000 0012
0000 0012
0000 0012
0000 0006
0000 0004
TSEG2
0001
0001
0001
0001
0001
0001
0001
0001
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