AT90CAN32 Automotive Atmel Corporation, AT90CAN32 Automotive Datasheet - Page 246

• Manufacturer Part Number: AT90CAN32 Automotive
• Manufacturer: Atmel Corporation

Specifications of AT90CAN32 Automotive

• Flash (kbytes): 32 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 53
• Ext Interrupts: 8
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 2
• Can: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 2
• Eeprom (bytes): 1024
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 125
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 4
• Output Compare Channels: 8
• Input Capture Channels: 2
• Pwm Channels: 7
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

19.6
19.6.1
19.6.2
19.6.3
19.6.4
19.7
19.7.1
246
CAN Timer
Error Management
AT90CAN32/64/128
Prescaler
16-bit Timer
Time Triggering
Stamping Message
Fault Confinement
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).
The CAN channel may be in one of the three following states:
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
IO
TTC
frequency divided by
SYNCTTC
7682C–AUTO–04/08
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