ATXMEGA256A3-MU Atmel, ATXMEGA256A3-MU Datasheet - Page 114

• Manufacturer Part Number: ATXMEGA256A3-MU
• Description: 8-bit Microcontrollers - MCU 8/16 bit 1.6V-3.6V 256KB + 8KB
• Manufacturer: Atmel

Specifications of ATXMEGA256A3-MU

• Product Category: 8-bit Microcontrollers - MCU
• Rohs: yes
• Core: AVR
• Data Bus Width: 8 bit/16 bit
• Maximum Clock Frequency: 32 MHz
• Program Memory Size: 256 KB
• Data Ram Size: 16 KB
• On-chip Adc: Yes
• Package / Case: QFN EP
• Mounting Style: SMD/SMT
• A/d Bit Size: 12 bit
• A/d Channels Available: 8
• Data Rom Size: 4 KB
• Interface Type: I2C, SPI, USART
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Number Of Programmable I/os: 50
• Number Of Timers: 7
• Processor Series: ATXMega
• Program Memory Type: Flash
• Factory Pack Quantity: 260
• Supply Voltage - Max: 3.6 V
• Supply Voltage - Min: 1.6 V

8068T–AVR–12/10
16. Pending full asynchronous pin change interrupts will not wake the device
17. Pin configuration does not affect Analog Comparator output
18. NMI Flag for Crystal Oscillator Failure automatically cleared
19. Crystal start-up time required after power-save even if crystal is source for RTC
20. RTC Counter value not correctly read after sleep
21. Pending asynchronous RTC-interrupts will not wake up device
Any full asynchronous pin-change Interrupt from pin 2, on any port, that is pending when the
sleep instruction is executed, will be ignored until the device is woken from another source
or the source triggers again. This applies when entering all sleep modes where the System
Clock is stopped.
Problem fix/Workaround
None.
The Output/Pull and inverted pin configuration does not affect the Analog Comparator
output.
Problem fix/Workaround
None for Output/Pull configuration.
For inverted I/O, configure the Analog Comparator to give an inverted result (i.e. connect
positive input to the negative AC input and vice versa), or use and external inverter to
change polarity of Analog Comparator output.
NMI flag for Crystal Oscillator Failure (XOSCFDIF) will be automatically cleared when exe-
cuting the NMI interrupt handler.
Problem fix/Workaround
This device revision has only one NMI interrupt source, so checking the interrupt source in
software is not required.
Even if 32.768 kHz crystal is used for RTC during sleep, the clock from the crystal will not be
ready for the system before the specified start-up time. See "XOSCSEL[3:0]: Crystal Oscilla-
tor Selection" in XMEGA A Manual. If BOD is used in active mode, the BOD will be on during
this period (0.5s).
Problem fix/Workaround
If faster start-up is required, go to sleep with internal oscillator as system clock.
If the RTC is set to wake up the device on RTC Overflow and bit 0 of RTC CNT is identical to
bit 0 of RTC PER as the device is entering sleep, the value in the RTC count register can not
be read correctly within the first prescaled RTC clock cycle after wakeup. The value read will
be the same as the value in the register when entering sleep.
The same applies if RTC Compare Match is used as wake-up source.
Problem fix/Workaround
Wait at least one prescaled RTC clock cycle before reading the RTC CNT value.
Asynchronous Interrupts from the Real-Time-Counter that is pending when the sleep
instruction is executed, will be ignored until the device is woken from another source or the
source triggers again.
Problem fix/Workaround
None.
XMEGA A3
114