ATxmega256A3U Atmel Corporation, ATxmega256A3U Datasheet - Page 446

• 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

33.12.3.2
33.12.3.3
33.12.3.4
33.12.3.5
8331A–AVR–07/11
Read NVM
Erase Page Buffer
Load Page Buffer
Erase Page
Once this operation starts, the PDIBUS between the PDI controller and the NVM is disabled,
and the NVMEN bit in the PDI STATUS register is cleared until the operation is finished. Poll the
NVMEN bit until this is set, indicating that the PDIBUS is enabled.
The BUSY flag in the NVM STATUS register will be set until the operation is finished.
The Read NVM command is used to read the Flash, EEPROM, Fuses, and Signature and Cali-
bration row sections.
Dedicated Read EEPROM, Read Fuse, Read Signature Row, and Read Calibration Row com-
mands are also available for the various memory sections. The algorithm for these commands
are the same as for the Read NVM command.
The Erase Flash Page Buffer and Erase EEPROM Page Buffer commands are used to erase
the Flash and EEPROM page buffers.
The BUSY flag in the NVM STATUS register will be set until the operation is completed.
The Load Flash Page Buffer and Load EEPROM Page Buffer commands are used to load one
byte of data into the Flash and EEPROM page buffers.
Since the Flash page buffer is word accessing and the PDI uses byte addressing, the PDI must
write the Flash Page Buffer in correct order. For the write operation, the low-byte of the word
location must be written before the high-byte. The low-byte is then written into the temporary
register. The PDI then writes the high-byte of the word location, and the low-byte is then written
into the word location page buffer in the same clock cycle.
The PDI interface is automatically halted, before the next PDI instruction can be executed.
The Erase Application Section Page, Erase Boot Loader Section Page, Erase User Signature
Row and Erase EEPROM Page commands are used to erase one page in the selected memory
space.
The BUSY flag in the NVM STATUS register will be set until the operation is finished.
1. Load the NVM CMD register with the Chip Erase command.
2. Set the CMDEX bit into NVM CTRLA register. This requires the timed CCP sequence
1. Load the NVM CMD register with the Read NVM command.
2. Read the selected memory address by executing a PDI Read operation.
1. Load the NVM CMD register with the Erase Flash/EEPROM Page Buffer command.
2. Set the CMDEX bit in the NVM CTRLA register.
1. Load the NVM CMD register with the Load Flash/EEPROM Page Buffer command.
2. Write the selected memory address by doing a PDI Write operation.
1. Load the NVM CMD register with Erase Application Section/Boot Loader Section/User
2. Set the CMDEX bit in the NVM CTRLA register
during self-programming.
Signature Row/EEPROM Page command.
Atmel AVR XMEGA AU
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