AT91SAM9263 Datasheet, PDF (655/1029 Pages) ATMEL Corporation – Thumb Microcontrollers

AT91SAM9263 Preliminary
If several mailboxes are chained to receive a buffer split into several messages, all mailboxes
except the last one (with the highest number) must be configured in Receive Mode. The first
message received is handled by the first mailbox, the second one is refused by the first mail-
box and accepted by the second mailbox, the last message is accepted by the last mailbox
and refused by previous ones (see Figure 37-13).
Figure 37-13. Chaining Three Mailboxes to Receive a Buffer Split into Three Messages
Buffer split in 3 messages
CAN BUS
MRDY
(CAN_MSRx)
MMI
(CAN_MSRx)
MRDY
(CAN_MSRy)
MMI
(CAN_MSRy)
MRDY
(CAN_MSRz)
MMI
(CAN_MSRz)
Message s1
Message s2
Message s3
Reading CAN_MSRx, CAN_MSRy and CAN_MSRz
Reading CAN_MDH & CAN_MDL for mailboxes x, y and z
Writing MBx MBy MBz in CAN_TCR
If the number of mailboxes is not sufficient (the MMI flag of the last mailbox raises), the user
must read each data received on the last mailbox in order to retrieve all the messages of the
buffer split (see Figure 37-14).
6249B–ATARM–14-Dec-06
655