Bxcan Interrupts; Figure 310. Can Frames - ST STM32F205 series Reference Manual

RM0033
Data Frame or
Remote Frame
End Of Frame or
Error Delimiter or
Overload Delimiter
27.8

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).
Inter-Frame Space
Arbitration Field
32
ID
Inter-Frame Space
Arbitration Field
32
ID
Inter-Frame Space
Arbitration Field
32
ID
Error Frame
Error
Flag Echo
Flag
6
6
Any Frame Inter-Frame Space
Suspend
Intermission
3 Transmission
8
Overload Frame
Overload Overload
Flag
Echo
6
6

Figure 310. CAN frames

Data Frame (Standard identifier)
44 + 8 * N
Ctrl Field Data Field
6 8 * N
DLC
Data Frame (Extended Identifier)
64 + 8 * N
Ctrl Field Data Field
Arbitration Field
6
32
DLC
Remote Frame
44
Ctrl Field CRC Field
6 16
DLC CRC
Inter-Frame Space
or Overload Frame
Error Delimiter
8
Data Frame or
Remote Frame
Bus Idle
Inter-Frame Space
or Error Frame
Overload
Delimiter
8
RM0033 Rev 8
Controller area network (bxCAN)
Inter-Frame Space
or Overload Frame
CRC Field Ack Field
2
16 7
CRC EOF
Inter-Frame Space
or Overload Frame
CRC Field Ack Field
2
8 * N 16
CRC
EOF
Inter-Frame Space
or Overload Frame
Ack Field
2
7
EOF
Notes:
0 <= N <= 8
SOF = Start Of Frame
ID = Identifier
RTR = Remote Transmission Request
IDE = Identifier Extension Bit
r0 = Reserved Bit
D LC = Data Length Code
C RC = Cyclic Redundancy Code
Error flag: 6 dominant bits if node is error
active else 6 recessive bits.
Suspend transmission: applies to error
passive nodes only.
EOF = End of Frame
ACK = Acknowledge bit
C trl = Control
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