AT91SAM7X128 Atmel, AT91SAM7X128 Datasheet - Page 521

• Manufacturer Part Number: AT91SAM7X128
• Description: MCU 32-Bit 91S ARM7TDMI RISC 128KB Flash 1.8V/3.3V 100-Pin LQFP
• Manufacturer: Atmel

Specifications of AT91SAM7X128

• Package: 100LQFP
• Device Core: ARM7TDMI
• Family Name: 91S
• Maximum Speed: 55 MHz
• Ram Size: 32 KB
• Program Memory Size: 128 KB
• Operating Supply Voltage: 1.8|3.3 V
• Data Bus Width: 32 Bit
• Program Memory Type: Flash
• Number Of Programmable I/os: 62
• Interface Type: CAN/Ethernet/SPI/I2S/TWI/USART/USB
• On-chip Adc: 8-chx10-bit
• Operating Temperature: -40 to 85 °C
• Number Of Timers: 3

36.7.2
6120H–ATARM–17-Feb-09
CAN Controller Interrupt Handling
Figure 36-10. Possible Initialization Procedure
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 register.
They can be unmasked by writing to the CAN_IER register. After a power-up reset, all interrupt
sources are disabled (masked). The current mask status can be checked by reading the
CAN_IMR register.
The CAN_SR register gives all interrupt source states.
The following events may initiate one of the two interrupts:
• Message object interrupt
• System interrupts
– Data registers in the mailbox object are available to the application. In Receive
– A sent transmission was aborted.
– 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, a new message was received. In Transmit Mode, a message was transmitted
successfully.
mode.
AT91SAM7X512/256/128 Preliminary
Configure a Mailbox in Reception Mode
Enable CAN Controller Interrupt Line
(ABM == 1 and CANEN == 1)
Enable CAN Controller Clock
(CAN_SR or CAN_MSRx)
ABM = 0 and CANEN = 0
CANEN = 1 (ABM == 0)
Change CAN_BR value
End of Initialization
Errors ?
(PMC)
(AIC)
No
Yes
521