ATMEGA64A-MNR Atmel, ATMEGA64A-MNR Datasheet - Page 382

• Manufacturer Part Number: ATMEGA64A-MNR
• Description: IC MCU AVR 64K FLASH 8QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA64A-MNR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• 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: *
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 2 KB
• Interface Type: SPI, UART, I2C
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 53
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 105 C
• Mounting Style: SMD/SMT
• Operating Temperature Range: - 40 C to + 85 C
• Processor To Be Evaluated: ATMEGA64A
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

34. Errata
34.1
8160C–AVR–07/09
ATmega64A, rev. D
The revision letter in this section refers to the revision of the ATmega64A device.
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1. First Analog Comparator conversion may be delayed
2. Interrupts may be lost when writing the timer registers in the asynchronous timer
3. Stabilizing time needed when changing XDIV Register
First Analog Comparator conversion may be delayed
Interrupts may be lost when writing the timer registers in the asynchronous timer
Stabilizing time needed when changing XDIV Register
Stabilizing time needed when changing OSCCAL Register
IDCODE masks data from TDI input
Reading EEPROM by using ST or STS to set EERE bit triggers unexpected interrupt request
If the device is powered by a slow rising V
take longer than expected on some devices.
Problem Fix/Workaround
When the device has been powered or reset, disable then enable theAnalog Comparator
before the first conversion.
The interrupt will be lost if a timer register that is synchronous timer clock is written when the
asynchronous Timer/Counter register (TCNTx) is 0x00.
Always check that the asynchronous Timer/Counter register neither have the value 0xFF nor
0x00 before writing to the asynchronous Timer Control Register (TCCRx), asynchronous
Timer Counter Register (TCNTx), or asynchronous Output Compare Register (OCRx).
After increasing the source clock frequency more than 2% with settings in the XDIV register,
the device may execute some of the subsequent instructions incorrectly.
Problem Fix / Workaround
The NOP instruction will always be executed correctly also right after a frequency change.
Thus, the next 8 instructions after the change should be NOP instructions. To ensure this,
follow this procedure:
1.Clear the I bit in the SREG Register.
2.Set the new pre-scaling factor in XDIV register.
3.Execute 8 NOP instructions
4.Set the I bit in SREG
This will ensure that all subsequent instructions will execute correctly.
Assembly Code Example:
CLI
OUT
NOP
NOP
NOP
NOP
NOP
NOP
Problem Fix / Workaround
XDIV, temp
; clear global interrupt enable
; set new prescale value
; no operation
; no operation
; no operation
; no operation
; no operation
; no operation
CC
, the first Analog Comparator conversion will
ATmega64A
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