ATxmega256A3BU Atmel Corporation, ATxmega256A3BU Datasheet - Page 435

• Manufacturer Part Number: ATxmega256A3BU
• Manufacturer: Atmel Corporation

Specifications of ATxmega256A3BU

• 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: 47
• Ext Interrupts: 49
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 8
• Twi (i2c): 2
• Uart: 6
• 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

33.11.2.2
33.11.2.3
33.11.2.4
33.11.2.5
33.11.2.6
8331A–AVR–07/11
Erase Flash Page Buffer
Load Flash Page Buffer
Erase Flash Page
Write Flash Page
Flash Range CRC
The Erase Flash Page Buffer command is used to erase the Flash Page Buffer.
The NVM Busy (BUSY) flag in the NVM Status Register (NVM STATUS) will be set until the
Page Buffer is erased.
The Load Flash Page Buffer command is used to load one word of data into the Flash Page
Buffer.
Repeat step 2-4 until the complete Flash Page Buffer is loaded. Unloaded locations will have the
value 0xFFFF.
The Erase Flash Page command is used to erase one page in the Flash.
The BUSY flag in the NVM STATUS register will be set until the erase operation is finished. The
Flash Section Busy (FBUSY) flag is set as long the Flash is Busy, and the Application section
cannot be accessed.
The Write Flash Page command is used to write the Flash Page Buffer into one flash page in the
Flash.
The BUSY flag in the NVM STATUS register will be set until the write operation is finished. The
FBUSY flag is set as long the Flash is Busy, and the Application section cannot be accessed.
The Flash Range CRC command can be used to verify the content in an address range in Flash
after a self-programming.
1. Load the NVM CMD with the Erase Flash Page Buffer command.
2. Set the Command Execute bit (NVMEX) in the NVM Control Register A (NVM CTRLA).
1. Load the NVM CMD register with the Load Flash Page Buffer command.
2. Load the Z-pointer with the word address to write.
3. Load the data word to be written into the R1:R0 registers.
4. Execute the SPM instruction. The SPM instruction is not protected when performing a
1. Load the Z-pointer with the flash page address to erase. The page address must be
2. Load the NVM CMD register with the Erase Flash Page command.
3. Execute the SPM instruction. This requires the timed CCP sequence during self-
1. Load the Z-pointer with the flash page to write. The page address must be written to
2. Load the NVM CMD register with the Write Flash Page command.
3. Execute the SPM instruction. This requires the timed CCP sequence during self-
1. Load the NVM CMD register with the Flash Range CRC command.
2. Load the start byte address in the NVM Address Register (NVM ADDR).
This requires the timed CCP sequence during self-programming.
Flash Page Buffer Load.
written to FPAGE. Other bits in the Z-pointer will be ignored during this operation.
programming.
FPAGE. Other bits in the Z-pointer will be ignored during this operation.
programming.
Atmel AVR XMEGA AU
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