ATMEGA32L-8AU Atmel, ATMEGA32L-8AU Datasheet - Page 184

• Manufacturer Part Number: ATMEGA32L-8AU
• Description: IC AVR MCU 32K 8MHZ 3V 44TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA32L-8AU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (16K x 16)
• 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: 44-TQFP, 44-VQFP
• Package: 44TQFP
• Device Core: AVR
• Family Name: ATmega
• Maximum Speed: 8 MHz
• Operating Supply Voltage: 3.3|5 V
• Data Bus Width: 8 Bit
• Number Of Programmable I/os: 32
• Interface Type: TWI/SPI/USART
• On-chip Adc: 8-chx10-bit
• Number Of Timers: 3
• Processor Series: ATMEGA32x
• Core: AVR8
• Data Ram Size: 2 KB
• Maximum Clock Frequency: 8 MHz
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Minimum Operating Temperature: - 40 C
• A/d Inputs: 8-Channel, 10-Bit
• Cpu Speed: 8 MIPS
• Eeprom Memory: 1K Bytes
• Input Output: 32
• Interface: I2C/SPI/UART/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 44-pin TQFP
• Programmable Memory: 32K Bytes
• Timers: 2-8-bit, 1-16-bit
• Voltage, Range: 2.7-5.5 V
• Data Rom Size: 1024 B
• Height: 1 mm
• Length: 10 mm
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2.7 V
• Width: 10 mm
• For Use With: ATSTK524 - KIT STARTER ATMEGA32M1/MEGA32C1ATSTK600-TQFP32 - STK600 SOCKET/ADAPTER 32-TQFPATSTK600-TQFP44 - STK600 SOCKET/ADAPTER 44-TQFPATSTK600-DIP40 - STK600 SOCKET/ADAPTER 40-PDIP770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1005 - ISP 4PORT FOR ATMEL AVR MCU JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPIATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVRATAVRISP2 - PROGRAMMER AVR IN SYSTEMATJTAGICE2 - AVR ON-CHIP D-BUG SYSTEMATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Table 74. Status Codes for Master Transmitter Mode
2503Q–AVR–02/11
Status Code
(TWSR)
Prescaler Bits
are 0
$08
$10
Status of the Two-wire Serial
Bus and Two-wire Serial Inter-
face Hardware
A START condition has been
transmitted
A repeated START condition
has been transmitted
A START condition is sent by writing the following value to TWCR:
TWEN must be set to enable the Two-wire Serial Interface, TWSTA must be written to one to
transmit a START condition and TWINT must be written to one to clear the TWINT Flag. The
TWI will then test the Two-wire Serial Bus and generate a START condition as soon as the bus
becomes free. After a START condition has been transmitted, the TWINT Flag is set by hard-
ware, and the status code in TWSR will be $08 (See
SLA+W must be transmitted. This is done by writing SLA+W to TWDR. Thereafter the TWINT bit
should be cleared (by writing it to one) to continue the transfer. This is accomplished by writing
the following value to TWCR:
When SLA+W have been transmitted and an acknowledgement bit has been received, TWINT is
set again and a number of status codes in TWSR are possible. Possible status codes in master
mode are $18, $20, or $38. The appropriate action to be taken for each of these status codes is
detailed in
When SLA+W has been successfully transmitted, a data packet should be transmitted. This is
done by writing the data byte to TWDR. TWDR must only be written when TWINT is high. If not,
the access will be discarded, and the Write Collision bit (TWWC) will be set in the TWCR Regis-
ter. After updating TWDR, the TWINT bit should be cleared (by writing it to one) to continue the
transfer. This is accomplished by writing the following value to TWCR:
This scheme is repeated until the last byte has been sent and the transfer is ended by generat-
ing a STOP condition or a repeated START condition. A STOP condition is generated by writing
the following value to TWCR:
A REPEATED START condition is generated by writing the following value to TWCR:
After a repeated START condition (state $10) the Two-wire Serial Interface can access the
same slave again, or a new slave without transmitting a STOP condition. Repeated START
enables the master to switch between slaves, master transmitter mode and master receiver
mode without losing control of the bus.
TWCR
Value
TWCR
Value
TWCR
Value
TWCR
Value
TWCR
Value
Table
To/from TWDR
Load SLA+W
Load SLA+W or
Load SLA+R
TWINT
TWINT
TWINT
TWINT
TWINT
1
1
1
1
1
74.
Application Software Response
TWEA
TWEA
TWEA
TWEA
TWEA
X
X
X
X
X
STA
0
0
0
TWSTA
TWSTA
TWSTA
TWSTA
TWSTA
1
0
0
0
1
STO
0
0
0
To TWCR
TWSTO
TWSTO
TWSTO
TWSTO
TWSTO
TWINT
0
0
0
1
0
1
1
1
TWEA
X
X
X
TWWC
TWWC
TWWC
TWWC
TWWC
X
X
X
X
X
Next Action Taken by TWI Hardware
SLA+W will be transmitted;
ACK or NOT ACK will be received
SLA+W will be transmitted;
ACK or NOT ACK will be received
SLA+R will be transmitted;
Logic will switch to Master Receiver mode
Table
TWEN
TWEN
TWEN
TWEN
TWEN
74). In order to enter MT mode,
1
1
1
1
1
ATmega32(L)
–
0
–
0
–
0
–
0
–
0
TWIE
TWIE
TWIE
TWIE
TWIE
X
X
X
X
X
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