ATMEGA64L-8AU Atmel, ATMEGA64L-8AU Datasheet - Page 60

• Manufacturer Part Number: ATMEGA64L-8AU
• Description: IC AVR MCU 64K 8MHZ 3V 64TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA64L-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: 53
• Program Memory Size: 64KB (32K x 16)
• 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
• Package: 64TQFP
• Device Core: AVR
• Family Name: ATmega
• Maximum Speed: 8 MHz
• Operating Supply Voltage: 2.5|3.3|5 V
• Data Bus Width: 8 Bit
• Number Of Programmable I/os: 53
• Interface Type: JTAG/SPI/TWI/USART
• On-chip Adc: 8-chx10-bit
• Number Of Timers: 4
• Processor Series: ATMEGA64x
• Core: AVR8
• Data Ram Size: 4 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
• Cpu Family: ATmega
• Device Core Size: 8b
• Frequency (max): 8MHz
• Total Internal Ram Size: 4KB
• # I/os (max): 53
• Number Of Timers - General Purpose: 4
• Operating Supply Voltage (typ): 2.5/3.3/5V
• Operating Supply Voltage (max): 5.5/5.8V
• Operating Supply Voltage (min): 2.4/2.7V
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 64
• Package Type: TQFP
• Controller Family/series: AVR MEGA
• No. Of I/o's: 53
• Eeprom Memory Size: 2KB
• Ram Memory Size: 4KB
• Cpu Speed: 8MHz
• Rohs Compliant: Yes
• For Use With: ATSTK600-TQFP64 - STK600 SOCKET/ADAPTER 64-TQFPATSTK600-TQFP32 - STK600 SOCKET/ADAPTER 32-TQFP770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1005 - ISP 4PORT FOR ATMEL AVR MCU JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPIATAVRISP2 - PROGRAMMER AVR IN SYSTEMATJTAGICE2 - AVR ON-CHIP D-BUG SYSTEMATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Timed Sequences
for Changing the
Configuration of
the Watchdog
Timer
Safety Level 0
Safety Level 1
Safety Level 2
2490Q–AVR–06/10
The sequence for changing configuration differs slightly between the three safety levels. Sepa-
rate procedures are described for each level.
This mode is compatible with the Watchdog operation found in ATmega103. The Watchdog
Timer is initially disabled, but can be enabled by writing the WDE bit to 1 without any restriction.
The Time-out period can be changed at any time without restriction. To disable an enabled
Watchdog Timer, the procedure described on
In this mode, the Watchdog Timer is initially disabled, but can be enabled by writing the WDE bit
to 1 without any restriction. A timed sequence is needed when changing the Watchdog Time-out
period or disabling an enabled Watchdog Timer. To disable an enabled Watchdog Timer, and/or
changing the Watchdog Time-out, the following procedure must be followed:
1. In the same operation, write a logic one to WDCE and WDE. A logic one must be written
2. Within the next four clock cycles, in the same operation, write the WDE and WDP bits as
In this mode, the Watchdog Timer is always enabled, and the WDE bit will always read as one. A
timed sequence is needed when changing the Watchdog Time-out period. To change the
Watchdog Time-out, the following procedure must be followed:
1. In the same operation, write a logical one to WDCE and WDE. Even though the WDE
2. Within the next four clock cycles, in the same operation, write the WDP bits as desired,
to WDE regardless of the previous value of the WDE bit.
desired, but with the WDCE bit cleared.
always is set, the WDE must be written to one to start the timed sequence.
but with the WDCE bit cleared. The value written to the WDE bit is irrelevant.
page 57
(WDE bit description) must be followed.
ATmega64(L)
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