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CP3BT26
A CAN data frame consists of the following fields:
Start of Frame (SOF)
Arbitration Field + Extended Arbitration
Control Field
Data Field
Cyclic Redundancy Check Field (CRC)
Acknowledgment Field (ACK)
End of Frame (EOF)
Remote Frame
Figure 38 shows the structure of a standard remote frame.
Figure 39 shows the structure of an extended remote frame.
Figure 38. Standard Remote Frame
Figure 39. Extended Remote Frame
A remote frame is comprised of the following fields, which is
the same as a data frame (see CAN Frame Fields on page
111) except for the data field, which is not present.
Start of Frame (SOF)
Arbitration Field + Extended Arbitration
Control Field
Cyclic Redundancy Check Field (CRC)
Acknowledgment field (ACK)
End of Frame (EOF)
Note that the DLC must have the same value as the corre-
sponding data frame to prevent contention on the bus. The
RTR bit is “recessive”.
STANDARD REMOTE FRAME (number of bits = 44)
Control Field END OF
FRAME
CRC Field
CRC
Arbitration Field
IDENTIFIER
10 ... 0
11
START OF FRAME
ID 10
ID0
ID3
RTR
IDE
RB0
dddd rrrrrrrrr
CRC DEL
ACK DEL
ACKNOWLEDGEMENT
154
16
DATA
LENGTH CODE
DLC3
DLC0
Note:
d = dominant
r = recessive
DS022
EXTENDED REMOTE FRAME (number of bits = 64)
Control Field END OF
FRAME
CRC Field
CRC
Arbitration Field
IDENTIFIER
28 ... 18
Note:
d = dominant
r = recessive
11 4
DATA
LENGTH CODE
START OF FRAME
ID 28
ID18
ID17
ID0
SRR
IDE
RTR
RB1
RB0
DLC3
DLC0
drr rdd rrrrrrrrr
CRC DEL
ACK DEL
SCK
18 15
16
IDENTIFIER
17 ... 0
DS023