cp3ub26 National Semiconductor Corporation, cp3ub26 Datasheet - Page 107

• Manufacturer Part Number: cp3ub26
• Description: Reprogrammable Connectivity Processor With Usb And Can Interfaces
• Manufacturer: National Semiconductor Corporation

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)
A remote frame is comprised of the following fields, which is
the same as a data frame (see CAN Frame Fields on page
105) 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”.
Note:
d = dominant
r = recessive
d
IDENTIFIER
28 ... 18
11
Note:
d = dominant
r = recessive
d
r r
Arbitration Field
Arbitration Field
IDENTIFIER
10 ... 0
11
Figure 29. Extended Remote Frame
Figure 28. Standard Remote Frame
EXTENDED REMOTE FRAME (number of bits = 64)
IDENTIFIER
STANDARD REMOTE FRAME (number of bits = 44)
17 ... 0
d d d
18
Control Field
LENGTH CODE
DATA
4
107
r d d
! Acknowledgment Field (ACK)
! End of Frame (EOF)
Remote Frame
Figure 28 shows the structure of a standard remote frame.
Figure 29 shows the structure of an extended remote frame.
Control Field
LENGTH CODE
CRC Field
CRC
DATA
15
16
4
r
CRC Field
CRC
15
r r
16
r r
END OF
FRAME
r r
DS022
r r
r
r r
r r
END OF
FRAME
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r r
DS023
r r