AT32UC3A3256 Atmel Corporation, AT32UC3A3256 Datasheet - Page 786

• Manufacturer Part Number: AT32UC3A3256
• Manufacturer: Atmel Corporation

Specifications of AT32UC3A3256

• Flash (kbytes): 256 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 66 MHz
• Cpu: 32-bit AVR
• # Of Touch Channels: 32
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 110
• Ext Interrupts: 110
• Usb Transceiver: 1
• Usb Speed: Hi-Speed
• Usb Interface: Device + OTG
• Spi: 6
• Twi (i2c): 2
• Uart: 4
• Lin: 4
• Ssc: 1
• Sd / Emmc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 384
• Resistive Touch Screen: No
• Dac Channels: 2
• Dac Resolution (bits): 16
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 128
• Self Program Memory: YES
• External Bus Interface: 1
• Dram Memory: sdram
• Nand Interface: Yes
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 3.0 to 3.6
• Operating Voltage (vcc): 3.0 to 3.6
• Fpu: No
• Mpu / Mmu: Yes / No
• Timers: 6
• Output Compare Channels: 18
• Input Capture Channels: 12
• Pwm Channels: 12
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

28.6.4
Figure 28-2. EOCn and DRDY Flag Behavior
32072G–11/2011
CHn(CHSR)
DRDY(SR)
EOCn(SR)
Conversion Results
With START=1
Write CR
as zero. The two highest bits of the Last Data Converted field in the Last Converted Data Regis-
ter (LCDR.LDATA) will be read as zero too.
Moreover, when a Peripheral DMA channel is connected to the ADC, a 10-bit resolution sets the
transfer request size to 16-bit. Writing a one to the LOWRES bit automatically switches to 8-bit
data transfers. In this case, the destination buffers are optimized.
When a conversion is completed, the resulting 10-bit digital value is stored in the CDR register of
the current channel and in the LCDR register. Channels are enabled by writing a one to the
Channel n Enable bit (CHn) in the CHER register.
The corresponding channel End of Conversion bit in the Status Register (SR.EOCn) and the
Data Ready bit in the SR register (SR.DRDY) are set. In the case of a connected Peripheral
DMA channel, DRDY rising triggers a data transfer request. In any case, either EOC or DRDY
can trigger an interrupt.
Reading one of the CDRn registers clears the corresponding EOC bit. Reading LCDR clears the
DRDY bit and the EOC bit corresponding to the last converted channel.
Conversion Time
Read CDRn
With START=1
Write CR
Conversion Time
Read LCDR
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