Controller area network (bxCAN)
RM0365
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DocID025202 Rev 7
•
The
FIFO 1 interrupt
can be generated by the following events:
–
Reception of a new message, FMP1 bits in the CAN_RF1R register are not ‘00’.
–
FIFO1 full condition, FULL1 bit in the CAN_RF1R register set.
–
FIFO1 overrun condition, FOVR1 bit in the CAN_RF1R register set.
•
The
error and status change interrupt
can be generated by the following events:
–
Error condition, for more details on error conditions refer to the CAN Error Status
register (CAN_ESR).
–
Wakeup condition, SOF monitored on the CAN Rx signal.
–
Entry into Sleep mode.
31.9 CAN
registers
The peripheral registers have to be accessed by words (32 bits).
31.9.1 Register
access
protection
Erroneous access to certain configuration registers can cause the hardware to temporarily
disturb the whole CAN network. Therefore the CAN_BTR register can be modified by
software only while the CAN hardware is in initialization mode.
Although the transmission of incorrect data will not cause problems at the CAN network
level, it can severely disturb the application. A transmit mailbox can be only modified by
software while it is in empty state, refer to
Figure 383: Transmit mailbox states
The filter values can be modified either deactivating the associated filter banks or by setting
the FINIT bit. Moreover, the modification of the filter configuration (scale, mode and FIFO
assignment) in CAN_FMxR, CAN_FSxR and CAN_FFAR registers can only be done when
the filter initialization mode is set (FINIT=1) in the CAN_FMR register.
31.9.2
CAN control and status registers
for a list of abbreviations used in register descriptions.
CAN master control register (CAN_MCR)
Address offset: 0x00
Reset value: 0x0001 0002
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
DBF
rw
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
RESET
Res.
Res.
Res.
Res.
Res.
Res.
Res.
TTCM
ABOM AWUM
NART
RFLM
TXFP
SLEEP
INRQ
rs
rw
rw
rw
rw
rw
rw
rw
rw