AT90CAN32-16AUR Atmel, AT90CAN32-16AUR Datasheet - Page 247

• Manufacturer Part Number: AT90CAN32-16AUR
• Description: MCU AVR 32K FLASH 16MHZ 64-TQFP
• Manufacturer: Atmel
• Series: AVR® 90CANr

Specifications of AT90CAN32-16AUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: CAN, EBI/EMI, I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP, 64-VQFP
• Data Bus Width: 8 bit
• Mounting Style: SMD/SMT
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATDVK90CAN1 - KIT DEV FOR AT90CAN128 MCU
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

19.6
19.6.1
19.6.2
19.6.3
19.6.4
7679H–CAN–08/08
CAN Timer
Prescaler
16-bit Timer
Time Triggering
Stamping Message
The data index (INDX) is the address pointer to the required data byte. The data byte can be
read or write. The data index is automatically incremented after every access if the AINC* bit is
reset. A roll-over is implemented, after data index=7 it is data index=0.
The first byte of a CAN frame is stored at the data index=0, the second one at the data index=1,
...
A programmable 16-bit timer is used for message stamping and time trigger communication
(TTC).
Figure 19-11. CAN Timer Block Diagram
An 8-bit prescaler is initialized by CANTCON register. It receives the clk
8. It provides clk
T
This timer starts counting from 0x0000 when the CAN controller is enabled (ENFG bit). When
the timer rolls over from 0xFFFF to 0x0000, an interrupt is generated (OVRTIM).
Two synchronization modes are implemented for TTC (TTC bit):
In TTC mode, a frame is sent once, even if an error occurs.
The capture of the timer value is done in the MOb which receives or sends the frame. All man-
aged MOb are stamped, the stamping of a received (sent) frame occurs on RxOk (TXOK).
clk
CANTIM
– synchronization on Start of Frame (SYNCTTC=0),
– synchronization on End of Frame (SYNCTTC=1).
RXOK[i]
TXOK[i]
clk
IO
=
T
OVRTIM
clk
CANTIM
IO
x 8 x (CANTCON [7:0] + 1)
8
frequency to the CAN Timer if the CAN controller is enabled.
CANSTM[i]
overrun
CANTCON
CANTIM
clk
CANTIM
ENFG
CANTTC
AT90CAN32/64/128
IO
TTC
frequency divided by
SYNCTTC
"EOF "
"SOF "
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