AT90CAN32 Automotive Atmel Corporation, AT90CAN32 Automotive Datasheet - Page 216

• 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

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Assembly Code Example
ldi
sts
wait1:
lds
sbrs
rjmp
lds
andi
cpi
brne
ldi
sts
ldi
sts
wait2:
lds
sbrs
rjmp
lds
andi
cpi
brne
ldi
sts
ldi
sts
wait3:
lds
sbrs
rjmp
lds
andi
cpi
brne
ldi
sts
AT90CAN32/64/128
r16, (1<<TWINT)|
TWCR, r16
r16,TWCR
r16,TWINT
wait1
r16,TWSR
r16, 0xF8
r16, START
ERROR
r16, SLA_W
TWDR, r16
r16, (1<<TWINT)|
TWCR, r16
r16,TWCR
r16,TWINT
wait2
r16,TWSR
r16, 0xF8
r16, MT_SLA_ACK
ERROR
r16, DATA
TWDR, r16
r16, (1<<TWINT)|
TWCR, r16
r16,TWCR
r16,TWINT
wait3
r16,TWSR
r16, 0xF8
r16, MT_DATA_ACK
ERROR
r16, (1<<TWINT)|
TWCR, r16
(1<<TWSTA)|
(1<<TWEN)
(1<<TWEN)
(1<<TWEN)
(1<<TWEN) |
(1<<TWSTO)
In the following an assembly and C implementation of the example is given. Note that the code
below assumes that several definitions have been made for example by using include-files.
• When the TWINT flag is set, the user must update all TWI Registers with the value relevant
• After all TWI Register updates and other pending application software tasks have been
for the next TWI bus cycle. As an example, TWDR must be loaded with the value to be
transmitted in the next bus cycle.
completed, TWCR is written. When writing TWCR, the TWINT bit should be set. Writing a
one to TWINT clears the flag. The TWI will then commence executing whatever operation
was specified by the TWCR setting.
C Example
TWCR = (1<<TWINT)|
while (!(TWCR & (1<<TWINT)));
if ((TWSR & 0xF8)!= START)
TWDR = SLA_W;
TWCR = (1<<TWINT)|(1<<TWEN);
while (!(TWCR & (1<<TWINT)));
if ((TWSR & 0xF8)!= MT_SLA_ACK)
TWDR = DATA;
TWCR = (1<<TWINT)|(1<<TWEN);
while (!(TWCR & (1<<TWINT)));
if ((TWSR & 0xF8)!=MT_DATA_ACK)
TWCR = (1<<TWINT)|
ERROR();
ERROR();
ERROR();
(1<<TWSTA)|
(1<<TWEN)
(1<<TWEN) |
(1<<TWSTO);
Comments
Send START condition
Wait for TWINT flag set. This indicates that
the START condition has been transmitted
Check value of TWI Status Register. Mask
prescaler bits. If status different from START
go to ERROR
Load SLA_W into TWDR Register. Clear
TWINT bit in TWCR to start transmission of
address
Wait for TWINT flag set. This indicates that
the SLA+W has been transmitted, and
ACK/NACK has been received.
Check value of TWI Status Register. Mask
prescaler bits. If status different from
MT_SLA_ACK go to ERROR
Load DATA into TWDR Register. Clear TWINT
bit in TWCR to start transmission of data
Wait for TWINT flag set. This indicates that
the DATA has been transmitted, and
ACK/NACK has been received.
Check value of TWI Status Register. Mask
prescaler bits. If status different from
MT_DATA_ACK go to ERROR
Transmit STOP condition
7682C–AUTO–04/08