RM0090: Reference manual - STMicroelectronics

RM0090 Controller area network (bxCAN)
Table 98. Transmit mailbox mapping
Offset to transmit mailbox base address Register name
Receive mailbox
When a message has been received, it is available to the software in the FIFO output
mailbox. Once the software has handled the message (e.g. read it) the software must
release the FIFO output mailbox by means of the RFOM bit in the CAN_RFR register to
make the next incoming message available. The filter match index is stored in the MFMI field
of the CAN_RDTxR register. The 16-bit time stamp value is stored in the TIME[15:0] field of
CAN_RDTxR.
Table 99. Receive mailbox mapping
Offset to receive mailbox base
address (bytes)
Figure 234. CAN error state diagram
0 CAN_TIxR
4 CAN_TDTxR
8 CAN_TDLxR
12 CAN_TDHxR
Register name
0 CAN_RIxR
4 CAN_RDTxR
8 CAN_RDLxR
12 CAN_RDHxR
ERROR ACTIVE
When 128 * 11 recessive bits occur:
When TEC or REC > 127
When TEC and REC < 128,
BUS OFF
ERROR PASSIVE
When TEC > 255
ai15903
Doc ID 018909 Rev 3 674/1416