AT90CAN128-15AZ Atmel, AT90CAN128-15AZ Datasheet - Page 216

• Manufacturer Part Number: AT90CAN128-15AZ
• Description: MCU AVR 128K FLASH 15MHZ 64TQFP
• Manufacturer: Atmel
• Series: AVR® 90CANr

Specifications of AT90CAN128-15AZ

• Package / Case: 64-TQFP, 64-VQFP
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Speed: 16MHz
• Number Of I /o: 53
• Eeprom Size: 4K x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 4K x 8
• Program Memory Size: 128KB (128K x 8)
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Connectivity: CAN, I²C, SPI, UART/USART
• Core Size: 8-Bit
• Processor Series: AT90CANx
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Interface Type: CAN, SPI, UART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 53
• Number Of Timers: 4
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATDVK90CAN1, ATADAPCAN01
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 8 Channel
• Cpu Family: 90C
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 16MHz
• Total Internal Ram Size: 4KB
• # I/os (max): 53
• Number Of Timers - General Purpose: 4
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 125C
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 64
• Package Type: TQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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AT90CAN32/64/128
Even though this example is simple, it shows the principles involved in all TWI transmissions.
These can be summarized as follows:
2. When the START condition has been transmitted, the TWINT flag in TWCR is set, and
3. The application software should now examine the value of TWSR, to make sure that
4. When the address packet has been transmitted, the TWINT flag in TWCR is set, and
5. The application software should now examine the value of TWSR, to make sure that
6. When the data packet has been transmitted, the TWINT flag in TWCR is set, and
7. The application software should now examine the value of TWSR, to make sure that
• When the TWI has finished an operation and expects application response, the TWINT flag is
set. The SCL line is pulled low until TWINT is cleared.
the application has cleared TWINT, the TWI will initiate transmission of the START
condition.
TWSR is updated with a status code indicating that the START condition has success-
fully been sent.
the START condition was successfully transmitted. If TWSR indicates otherwise, the
application software might take some special action, like calling an error routine.
Assuming that the status code is as expected, the application must load SLA+W into
TWDR. Remember that TWDR is used both for address and data. After TWDR has
been loaded with the desired SLA+W, a specific value must be written to TWCR,
instructing the TWI hardware to transmit the SLA+W present in TWDR. Which value to
write is described later on. However, it is important that the TWINT bit is set in the value
written. Writing a one to TWINT clears the flag. The TWI will not start any operation as
long as the TWINT bit in TWCR is set. Immediately after the application has cleared
TWINT, the TWI will initiate transmission of the address packet.
TWSR is updated with a status code indicating that the address packet has success-
fully been sent. The status code will also reflect whether a slave acknowledged the
packet or not.
the address packet was successfully transmitted, and that the value of the ACK bit was
as expected. If TWSR indicates otherwise, the application software might take some
special action, like calling an error routine. Assuming that the status code is as
expected, the application must load a data packet into TWDR. Subsequently, a specific
value must be written to TWCR, instructing the TWI hardware to transmit the data
packet present in TWDR. Which value to write is described later on. However, it is
important that the TWINT bit is set in the value written. Writing a one to TWINT clears
the flag. The TWI will not start any operation as long as the TWINT bit in TWCR is set.
Immediately after the application has cleared TWINT, the TWI will initiate transmission
of the data packet.
TWSR is updated with a status code indicating that the data packet has successfully
been sent. The status code will also reflect whether a slave acknowledged the packet
or not.
the data packet was successfully transmitted, and that the value of the ACK bit was as
expected. If TWSR indicates otherwise, the application software might take some spe-
cial action, like calling an error routine. Assuming that the status code is as expected,
the application must write a specific value to TWCR, instructing the TWI hardware to
transmit a STOP condition. Which value to write is described later on. However, it is
important that the TWINT bit is set in the value written. Writing a one to TWINT clears
the flag. The TWI will not start any operation as long as the TWINT bit in TWCR is set.
Immediately after the application has cleared TWINT, the TWI will initiate transmission
of the STOP condition. Note that TWINT is NOT set after a STOP condition has been
sent.
7679H–CAN–08/08