Figure 192. Can Block Diagram - ST STM32F102 Series Reference Manual

RM0008
Control, status and configuration registers
The application uses these registers to:
●
Configure CAN parameters, e.g. baud rate
●
Request transmissions
●
Handle receptions
● Manage interrupts
●
Get diagnostic information
Tx mailboxes
Three transmit mailboxes are provided to the software for setting up messages. The
transmission Scheduler decides which mailbox has to be transmitted first.
Acceptance filters
The bxCAN provides 14 scalable/configurable identifier filter banks for selecting the
incoming messages the software needs and discarding the others.
Receive FIFO
Two receive FIFOs are used by hardware to store the incoming messages. Three complete
messages can be stored in each FIFO. The FIFOs are managed completely by hardware.

Figure 192. CAN block diagram

Master Control
Master Status
Transmit Control
Transmit Status
Transmit Priority
Receive FIFO
Interrupt Enable
Error Status
Error Int. Enable
Tx Error Counter
Rx Error Counter
Diagnostic
Bit Timing
Filter Mode
Filter Config.
Tx Mailboxes Receive FIFO 0
Mailbox 2
Mailbox 1
Mailbox 0
Transmission
Filter
Scheduler
CAN 2.0B Active Core
Controller area network (bxCAN)
Receive FIFO 1
2
1
Mailbox 0
Acceptance Filters
3
2
1
0
2
1
Mailbox 0
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