Can Operation - Analog Devices ADSP-BF506F Hardware Reference Manual

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Due to the inherent nature of the CAN protocol, a dominant bit in
the
RTR
( = ) for the same message ID, thereby defining a remote request
RTR 1
to be lower priority than a data frame.
The next field of interest is the
sage is an extended frame with a 29-bit identifier instead of an 11-bit
identifier. In an extended frame, the first part of the message resembles
Figure 17-6.
1
SOF IDENTIFIER SRR
Figure 17-6. Extended CAN Frame
As could be concluded with regards to the
field wins arbitration against an extended frame with the same lower
IDE
11-bits, therefore, standard frames are higher priority than extended
frames. The substitute remote request bit (
the reserved bits
( ) are generated automatically by the internal logic.
CRC

CAN Operation

The CAN controller is in configuration mode when coming out of proces-
sor reset or hibernate. It is only when the CAN is in configuration mode
that hardware behavior can be altered. Before initializing the mailboxes
themselves, the CAN bit timing must be set up to work on the CAN bus
that the controller is expected to connect to.
ADSP-BF50x Blackfin Processor Hardware Reference
field wins arbitration against a remote frame request
IDE
11 1 1 18
IDE IDENTIFIER
and (always sent as dominant), and the checksum
r0 r1
. When set, it indicates that the mes-
1 1 1 4
RTR r1 r0 DLC
field, a dominant bit in the
RTR
, always sent as recessive),
SRR
CAN Module
17-9