Controller area network (bxCAN)
RM0090
1086/1731
DocID018909 Rev 11
Figure 347. CAN frames
32.8 bxCAN
interrupts
Four interrupt vectors are dedicated to bxCAN. Each interrupt source can be independently
enabled or disabled by means of the CAN Interrupt Enable Register (CAN_IER).
Data Frame or
Remote Frame
Data Field
8 * N
Ctrl Field
6
Ar
b
itration Field
32
CRC Field
16
Ack Field
7
SOF
ID
DLC
CRC
Data Frame (Standard identifier)
44 + 8 * N
Ar
b
itration Field
32
RT
R
IDE
r0
SOF
ID
DLC
Remote Frame
44
CRC Field
16
7
CRC
Ctrl Field
6
Overload
Overload Frame
Error
6
Error Delimiter
8
Error Frame
Flag Echo
6
Bus Idle
Inter-Frame Space
Suspend
8
Intermission
3
Transmission
AC
K
AC
K
2
2
Inter-Frame Space
or Overload Frame
Inter-Frame Space
Inter-Frame Space
or Overload Frame
Inter-Frame Space
Inter-Frame Space
or Overload Frame
Notes:
0
<=
N
<=
8
SOF = Start Of Frame
ID = Identifier
RTR = Remote Transmission Re
q
uest
IDE = Identifier Extension Bit
r0 = Reserved Bit
DLC = Data Length Code
CRC = Cyclic Redundancy Code
Error flag: 6 dominant
b
its if node is error
active else 6 recessive
b
its.
Suspend transmission: applies to error
passive nodes only.
EOF = End of Frame
ACK = Acknowledge
b
it
Ctrl = Control
Data Frame or
Remote Frame
Any Frame
Inter-Frame Space
or Error Frame
End Of Frame or
Error Delimiter or
Overload Delimiter
Ack Field
EOF
RT
R
ID
E
r0
EOF
Data Field
8 * N
Ctrl Field
6
32
CRC Field
16
Ack Field
7
SO
F
ID
DLC
CRC
Data Frame (Extended Identifier)
64 + 8 * N
AC
K
2
Inter-Frame Space
or Overload Frame
Inter-Frame Space
SRR
IDE
EOF
RT
R r1
r0
32
6
Overload
8
6
Overload
Flag
Echo
Delimiter
Flag
ai15154
Ar
b
itration Field
Ar
b
itration Field