Datasheet
524
SAM7X Series [DATASHEET]
6120K–ATARM–11-Feb-14
36.8.12 CAN Message Mode Register
Name: CAN_MMRx
Access Type: Read-write
• MTIMEMARK: Mailbox Timemark
This field is active in Time Triggered Mode. Transmit operations are allowed when the internal timer counter reaches the Mailbox
Timemark. See “Transmitting within a Time Window” on page 504.
In Timestamp Mode, MTIMEMARK is set to 0.
• PRIOR: Mailbox Priority
This field has no effect in receive and receive with overwrite modes. In these modes, the mailbox with the lowest number is ser-
viced first.
When several mailboxes try to transmit a message at the same time, the mailbox with the highest priority is serviced first. If sev-
eral mailboxes have the same priority, the mailbox with the lowest number is serviced first (i.e., MBx0 is serviced before MBx 15 if
they have the same priority).
• MOT: Mailbox Object Type
This field allows the user to define the type of the mailbox. All mailboxes are independently configurable. Five different types are
possible for each mailbox:
31 30 29 28 27 26 25 24
–––––
MOT
23 22 21 20 19 18 17 16
–––– PRIOR
15 14 13 12 11 10 9 8
MTIMEMARK15 MTIMEMARK14 MTIMEMARK13 MTIMEMARK12 MTIMEMARK11 MTIMEMARK10 MTIMEMARK9 MTIMEMARK8
76543210
MTIMEMARK7 MTIMEMARK6 MTIMEMARK5 MTIMEMARK4 MTIMEMARK3 MTIMEMARK2 MTIMEMARK1 MTIMEMARK0
MOT Mailbox Object Type
000
Mailbox is disabled. This prevents receiving or transmitting any messages
with this mailbox.
001
Reception Mailbox. Mailbox is configured for reception. If a message is
received while the mailbox data register is full, it is discarded.
010
Reception mailbox with overwrite. Mailbox is configured for reception. If a
message is received while the mailbox is full, it overwrites the previous
message.
0 1 1 Transmit mailbox. Mailbox is configured for transmission.
100
Consumer Mailbox. Mailbox is configured in reception but behaves as a
Transmit Mailbox, i.e., it sends a remote frame and waits for an answer.
101
Producer Mailbox. Mailbox is configured in transmission but also behaves
like a reception mailbox, i.e., it waits to receive a Remote Frame before
sending its contents.
1 1 X Reserved