AT90CAN64-16AUR Atmel, AT90CAN64-16AUR Datasheet - Page 217

• Manufacturer Part Number: AT90CAN64-16AUR
• Description: MCU AVR 64K FLASH 16MHZ 64TQFP
• Manufacturer: Atmel
• Series: AVR® 90CANr

Specifications of AT90CAN64-16AUR

• 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: 64KB (64K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 4K 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
• Data Ram Size: 4 KB
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

7679H–CAN–08/08
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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
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
AT90CAN32/64/128
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