AT32WB415
Series Reference Manual
2022.04.13
Page 285
Ver 2.00
0: Error passive state is not entered
1: Error passive state is entered
Note: This bit is set by hardware when the current error
times has reached the Error passive state limit (Receive
Error Counter or Transmit Error Counter >127)
Bit 0
EAF
0x0
ro
Error active flag
0: Error active state is not entered
1: Error active state is entered
Note: This bit is set by hardware when the current error
times has reached the Error active state limit (Receive
Error Counter or Transmit Error Counter ≥96)
19.7.1.8 CAN bit timing register (CAN_BTMG)
Bit
Register
Reset value
Type
Description
Bit 31
LOEN
0x0
rw
Listen-Only mode
0: Listen-Only mode disabled
1: Listen-Only mode enabled
Bit 30
LBEN
0x0
rw
Loop back mode
0: Loop back mode disabled
1: Loop back mode enabled
Bit 29: 26 Reserved
0x0
resd
Kept at its default value.
Bit 25: 24 RSAW
0x1
rw
Resynchronization width
tRSAW = tCAN x (RSAW[1: 0] + 1
)
Note: This field defines the maximum of time unit that the
CAN handware is allowed to lengthen or shorten in a bit.
Bit 23
Reserved
0x0
resd
Kept at its default value.
Bit 22: 20 BTS2
0x2
rw
Bit time segment 2
tBTS2 = tCAN x (BTS2[2: 0] + 1)
Note: This field defines the number of time unit in Bit time
segment 2.
Bit 19: 16 BTS1
0x3
rw
Bit time segment 1
tBTS1 = tCAN x (BTS1[3: 0] + 1)
Note: This field defines the number of time unit in Bit time
segment 1.
Bit 15: 12 Reserved
0x0
resd
Kept at its default value.
Bit 11: 0
BRDIV
0x000
rw
Baud rate division
tq = (BRDIV[11: 0]+1) x tPCLK
Note: This field defines the length of a time unit (tq).
19.7.2 CAN mailbox registers
This section describes the registers of the transmit and receive mailboxes. Refer to
section 19.6.5
for
more information on register map.
Transmit and receive mailboxes are the same except:
RFFMN field in the CAN_RFCx register
A receive mailbox is read only
A transmit mailbox can be written only when empty. TM2S=1 in the CAN_TSTS register indicates
that the mailbox is empty.
There are three transmit mailboxes and two receive mailboxes. Each receive mailbox has 3-level depth
of FIFO, and can only access to the first received message in the FIFO.
Each mailbox contains four registers.
Figure 19-14 Transmit and receive mailboxes
CAN_RFI0
CAN_RDT0
CAN_RDL0
CAN_RDH0
CAN_RFI0
CAN_RDT0
CAN_RDL0
CAN_RDH0
CAN_RFI0
FIFO0
CAN_RFC0
CAN_RFDTL0
CAN_RFDTH0
CAN_RFI0
CAN_RDT0
CAN_RDL0
CAN_RDH0
CAN_RFI0
CAN_RDT0
CAN_RDL0
CAN_RDH0
CAN_RFI1
FIFO1
CAN_RFC1
CAN_RFDTL1
CAN_RFDTH1
CAN_TMI0
CAN_TMC0
CAN_TMDTL0
CAN_TMDTH0
CAN_TMI1
CAN_TMC1
CAN_TMDTL1
CAN_TMDTH1
CAN_TMI2
CAN_TMC2
CAN_TMDTL2
CAN_TMDTH2
Transmit mailboxes