Table 182. Transmit Mailbox Mapping; Table 183. Receive Mailbox Mapping - ST STM32F405 Reference Manual

RM0090
32.7.5 Message storage
The interface between the software and the hardware for the CAN messages is
implemented by means of mailboxes. A mailbox contains all information related to a
message; identifier, data, control, status and time stamp information.
Transmit mailbox
The software sets up the message to be transmitted in an empty transmit mailbox. The
status of the transmission is indicated by hardware in the CAN_TSR register.
Offset to transmit mailbox base address (bytes)
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.
Offset to receive mailbox base address (bytes)

Table 182. Transmit mailbox mapping

0
4
8
12

Table 183. Receive mailbox mapping

0
4
8
12
RM0090 Rev 18
Controller area network (bxCAN)
Register name
CAN_TIxR
CAN_TDTxR
CAN_TDLxR
CAN_TDHxR
Register name
CAN_RIxR
CAN_RDTxR
CAN_RDLxR
CAN_RDHxR
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