AT91SAM7X128 Atmel, AT91SAM7X128 Datasheet - Page 530

• 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

Figure 36-18. Consumer Handling
36.7.4
36.7.4.1
Figure 36-19. Mailbox Timestamp
6120H–ATARM–17-Feb-09
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
AT91SAM7X512/256/128 Preliminary
End of Frame
Message x
Remote Frame
Message 2
Message y
Timestamp 2
Timestamp 2
Message y
530