ATxmega256A3U Atmel Corporation, ATxmega256A3U Datasheet - Page 326

• 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

26.5
26.6
8331A–AVR–07/11
CRC on DMA Data
CRC using the I/O Interface
CRC-16 or CRC-32 calculations can be performed on data passing through any DMA channel.
Once a DMA channel is selected as the source, the CRC module will continuously generate the
CRC on the data passing through the DMA channel. The checksum is available for readout once
the DMA transaction is completed or aborted. A CRC can be performed not only on communica-
tion data, but also on data in SRAM or I/O memory by passing these data through a DMA
channel. If the latter is done, the destination register for the DMA data can be the data input
(DATAIN) register in the CRC module. Refer to
for more details on setting up DMA transactions.
CRC can be performed on any data by loading them into the CRC module using the CPU and
writing the data to the DATAIN register. Using this method, an arbitrary number of bytes can be
written to the register by the CPU, and CRC is done continuously for each byte. New data can
be written for each cycle, or whenever new data or the CPU is available to load more data. The
CRC complete is signaled by writing to the BUSY bit in the STATUS register.
”DAC - Digital to Analog Converter” on page 382
Atmel AVR XMEGA AU
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