ATxmega256A3U Atmel Corporation, ATxmega256A3U Datasheet - Page 122

• Manufacturer Part Number: ATxmega256A3U
• Manufacturer: Atmel Corporation

Specifications of ATxmega256A3U

• Flash (kbytes): 256 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 32 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 50
• Ext Interrupts: 50
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 10
• Twi (i2c): 2
• Uart: 7
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 16
• Adc Resolution (bits): 12
• Adc Speed (ksps): 2000
• Analog Comparators: 4
• Resistive Touch Screen: No
• Dac Channels: 2
• Dac Resolution (bits): 12
• Temp. Sensor: Yes
• Crypto Engine: AES/DES
• Sram (kbytes): 16
• Eeprom (bytes): 4096
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.6 to 3.6
• Operating Voltage (vcc): 1.6 to 3.6
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 7
• Output Compare Channels: 22
• Input Capture Channels: 22
• Pwm Channels: 22
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

10.5.2
8331A–AVR–07/11
Main Power Restore and Start-up Sequence
At every startup after main power is restored, the software should:
1. Control the main reset source to determine that a POR or BOD took place.
2. Check for power on the V
3. Read the power supervisor flags to determine further software action:
a. If all power supervision flags are cleared, the battery backup system runs as nor-
b. If any power supervision flags are set, it indicates the battery backup system has
mal. The software should enable access to the battery backup system and check
the crystal oscillator failure flag. If the flag is set, the software should assume that
the RTC counter value is invalid and take appropriate action.
lost power sometime during the period when the rest of the device was unpower-
erd. Software should assume that the configuration and RTC value are invalid and
take appropriate action.
BAT
pin by reading the BBPWR flag.
Atmel AVR XMEGA AU
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