at91sam9263 ATMEL Corporation, at91sam9263 Datasheet - Page 681

• Manufacturer Part Number: at91sam9263
• Description: At91 Arm Thumb Microcontrollers
• Manufacturer: ATMEL Corporation

Figure 37-18. Consumer Handling
37.7.4
37.7.4.1
Figure 37-19. Mailbox Timestamp
6249D–ATARM–20-Dec-07
MTIMESTAMP
MTIMESTAMP
(CAN_MCRx)
(CAN_MSRx)
(CAN_MSRx)
TIMESTAMP
(CAN_TSTP)
CAN_MDHx)
(CAN_MSRx)
(CAN_MDLx
(CAN_MSRy)
(CAN_MR)
CAN BUS
CAN BUS
CAN_TIM
TEOF
MRDY
MTCR
MMI
CAN Controller Timing Modes
Timestamping Mode
Using the free running 16-bit internal timer, the CAN controller can be set in one of the two fol-
lowing timing modes:
Timestamping Mode is enabled by clearing the TTM bit in the CAN_MR register. Time Triggered
Mode is enabled by setting the TTM bit in the CAN_MR register.
Each mailbox has its own timestamp value. Each time a message is sent or received by a mail-
box, the 16-bit value MTIMESTAMP of the CAN_TIMESTP register is transferred to the LSB bits
of the CAN_MSRx register. The value read in the CAN_MSRx register corresponds to the inter-
nal timer value at the Start Of Frame or the End Of Frame of the message handled by the
mailbox.
Remote Frame
Timestamp 1
• Timestamping Mode: The value of the internal timer is captured at each Start Of Frame or
• Time Triggered Mode: The mailbox transfer operation is triggered when the internal timer
Timestamp 1
Message 1
each End Of Frame.
reaches the mailbox trigger.
Start of Frame
Message x
End of Frame
Message x
Remote Frame
AT91SAM9263 Preliminary
Message 2
Message y
Timestamp 2
Timestamp 2
Message y
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