Atmel Xplained Pro Evaluation Kit ATSAM4E-XPRO ATSAM4E-XPRO Data Sheet

669

SAM4E [DATASHEET]

Atmel-11157D-ATARM-SAM4E16-SAM4E8-Datasheet_12-Jun-14

There are two different types of interrupts. One type of interrupt is a message-object related interrupt, the other is
a system interrupt that handles errors or system-related interrupt sources.

All interrupt sources can be masked by writing the corresponding field in the CAN_IDR. They can be unmasked by
writing to the CAN_IER. After a power-up reset, all interrupt sources are disabled (masked). The current mask
status can be checked by reading the CAN_IMR.

The CAN_SR gives all interrupt source states. 

The following events may initiate one of the two interrupts:



Message object interrupt

̶

Data registers in the mailbox object are available to the application. In Receive Mode, a new message 
was received. In Transmit Mode, a message was transmitted successfully. 

̶

A sent transmission was aborted.



System interrupts

̶

Bus off interrupt: The CAN module enters the bus off state.

̶

Error passive interrupt: The CAN module enters Error Passive Mode.

̶

Error Active Mode: The CAN module is neither in Error Passive Mode nor in Bus Off mode.

̶

Warn Limit interrupt: The CAN module is in Error-active Mode, but at least one of its error counter 
value exceeds 96.

̶

Wake-up interrupt: This interrupt is generated after a wake-up and a bus synchronization.

̶

Sleep interrupt: This interrupt is generated after a Low-power Mode enable once all pending 
messages in transmission have been sent.

Errors ?

No

Yes

(ABM == 1 and CANEN == 1)

CANEN = 1 (ABM ==  0)

ABM = 0 and CANEN = 0

(CAN_SR or CAN_MSRx)

Change CAN_BR value

End of Initialization

Configure a Mailbox in Reception Mode

Enable CAN Controller Interrupt Line

Enable CAN Controller Clock

(Interrupt Controller)

(PMC)