ATxmega64A1 Atmel Corporation, ATxmega64A1 Datasheet - Page 365

• Manufacturer Part Number: ATxmega64A1
• Manufacturer: Atmel Corporation

Specifications of ATxmega64A1

• Flash (kbytes): 64 Kbytes
• Pin Count: 100
• Max. Operating Frequency: 32 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 78
• Ext Interrupts: 78
• Usb Speed: No
• Usb Interface: No
• Spi: 12
• Twi (i2c): 4
• Uart: 8
• 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: 4
• Dac Resolution (bits): 12
• Temp. Sensor: Yes
• Crypto Engine: AES/DES
• Sram (kbytes): 4
• Eeprom (bytes): 2048
• Self Program Memory: YES
• External Bus Interface: 1
• Dram Memory: sdram
• 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: 8
• Output Compare Channels: 24
• Input Capture Channels: 24
• Pwm Channels: 24
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

30.7
30.7.1
30.7.2
8077H–AVR–12/09
Flash and EEPROM Programming Sequences
Flash Programming Sequence
EEPROM programming sequence
The EEPROM Page Buffer is automatically erased after:
For Flash and EEPROM page programming, filling the page buffers and writing the page buffer
into Flash or EEPROM is two separate operations. The sequence of this is the same for both
self-programming and external programming.
Before programming a Flash page with the data in the Flash page buffer, the Flash page must
be erased. Programming an un-erased flash Page will corrupt the content in the flash Page.
The flash page buffer can be filled either before the Erase Flash Page operation or between a
Erase Flash Page and a Write Flash Page operation:
Alternative 1, fill the buffer before a split Page Erase and Page Write:
Alternative 2, fill the page buffer before an atomic Page Erase and Write:
Alternative 3, fill the buffer after a Page Erase:
The NVM command set supports both atomic erase and write operations, and split page erase
and page write commands. This split commands enables shorter programming time for each
command and the erase operations can be done during non-time-critical programming execu-
tion. When using alternative 1 or 2 above for self-programming, the Boot Loader provides an
effective Read-Modify-Write feature, which allows the software to first read the page, do the nec-
essary changes, and then write back the modified data. If alternative 3 is used, it is not possible
to read the old data while loading, since the page is already erased. The page address must be
the same for both Page Erase and Page Write operations when using alternative 1 or 3.
Before programming an EEPROM page with the selected number of data bytes stored in the
EEPROM page buffer, the selected locations in the EEPROM page must be erased. Program-
ming an un-erased EEPROM page will corrupt the content in the EEPROM page. The EEPROM
page buffer must be loaded before any Page Erase or Page Write operations:
Alternative 1, fill the page buffer before a Page Erase:
• A system reset.
• Executing the Write EEPROM Page command.
• Executing the Erase and Write EEPROM Page command.
• Executing the Write Lock Bit and Write Fuse commands
• Fill the Flash Page Buffer.
• Perform a Flash Page Erase.
• Perform a Flash Page Write.
• Fill the Flash Page Buffer.
• Perform a Page Erase and Write.
• Perform a Flash Page Erase.
• Fill the Flash Page Buffer.
• Perform a Flash Page Write.
• Fill the EEPROM page buffer with the selected number of bytes.
XMEGA A
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