ATxmega16A4U Atmel Corporation, ATxmega16A4U Datasheet - Page 56

• Manufacturer Part Number: ATxmega16A4U
• Manufacturer: Atmel Corporation

Specifications of ATxmega16A4U

• Flash (kbytes): 16 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 32 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 34
• Ext Interrupts: 34
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 7
• Twi (i2c): 2
• Uart: 5
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 12
• Adc Resolution (bits): 12
• Adc Speed (ksps): 2000
• Analog Comparators: 2
• Resistive Touch Screen: No
• Dac Channels: 2
• Dac Resolution (bits): 12
• Temp. Sensor: Yes
• Crypto Engine: AES/DES
• Sram (kbytes): 3.3
• Eeprom (bytes): 1024
• 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: 5
• Output Compare Channels: 16
• Input Capture Channels: 16
• Pwm Channels: 16
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

5.8
5.9
5.10
5.11
5.12
8331A–AVR–07/11
Transfer Buffers
Error detection
Software Reset
Protection
Interrupts
To avoid unnecessary bus loading when doing data transfer between memories with different
access timing (for example, I/O register and external memory), the DMA controller has a four-
byte buffer. Two bytes will be read from the source address and written to this buffer before a
write to the destination is started.
The DMA controller can detect erroneous operation. Error conditions are detected individually
for each DMA channel, and the error conditions are:
Both the DMA controller and a DMA channel can be reset from the user software. When the
DMA controller is reset, all registers associated with the DMA controller, including channels, are
cleared. A software reset can be done only when the DMA controller is disabled.
When a DMA channel is reset, all registers associated with the DMA channel are cleared. A soft-
ware reset can be done only when the DMA channel is disabled.
In order to ensure safe operation, some of the channel registers are protected during a transac-
tion. When the DMA channel busy flag (CHnBUSY) is set for a channel, the user can modify only
the following registers and bits:
The DMA controller can generate interrupts when an error is detected on a DMA channel or
when a transaction is complete for a DMA channel. Each DMA channel has a separate interrupt
vector, and there are different interrupt flags for error and transaction complete.
If repeat is not enabled, the transaction complete flag is set at the end of the block transfer. If
unlimited repeat is enabled, the transaction complete flag is also set at the end of each block
transfer.
• Write to memory mapped EEPROM locations
• Reading EEPROM when the EEPROM is off (sleep entered)
• DMA controller or a busy channel is disabled in software during a transfer
• CTRL register
• INTFLAGS register
• TEMP registers
• CHEN, CHRST, TRFREQ, and REPEAT bits of the channel CTRL register
• TRIGSRC register
Atmel AVR XMEGA AU
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