ATxmega16D4 Atmel Corporation, ATxmega16D4 Datasheet - Page 276

• Manufacturer Part Number: ATxmega16D4
• Manufacturer: Atmel Corporation

Specifications of ATxmega16D4

• 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 Speed: No
• Usb Interface: No
• Spi: 4
• Twi (i2c): 2
• Uart: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 12
• Adc Resolution (bits): 12
• Adc Speed (ksps): 200
• Analog Comparators: 2
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 2
• 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: 4
• Output Compare Channels: 14
• Input Capture Channels: 14
• Pwm Channels: 14
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

23.8
23.9
23.9.1
23.9.2
23.10 Self-Programming and Boot Loader Support
23.10.1
8210B–AVR–04/10
Protection of NVM
Preventing NVM Corruption
Write Corruption
Read Corruption
Flash Programming
Alternative 1, fill the page buffer before a Page Erase:
Alternative 2, fill the buffer before a Page Erase and Write:
To protect the Flash and EEPROM memories from write and/or read, Lock Bits can be set to
restrict access from external programmers and the Application Software. Refer to
Non-Volatile Memory Lock Bit Register” on page 29
and how to use them.
During periods when the V
result from a Flash memory read or write can be corrupt as supply voltage is too low for the CPU
and the Flash to operate properly.
To ensure that the voltage is correct during a complete write sequence to the Flash memory, the
BOD is automatically enabled by hardware when the write sequence starts. If a BOD reset
occurs, the programming sequence will be aborted immediately. If this happens, the NVM pro-
gramming should be restarted when the power is sufficient again in case the write sequence
failed or only partly succeeded.
The NVM can be read incorrectly if the supply voltage is too low so the CPU execute instructions
incorrectly. To ensure that this does not happen the BOD can be enabled.
Both the EEPROM and the Flash memory can be read and written from the application software
in the device. This is referred to as self-programming. A Boot Loader (Application code located
in the Boot Loader Section of the Flash) can both read and write the Flash Program Memory,
User Signature Row and EEPROM, and write the Lock Bits to a more secure setting. Application
code in both the Application Section can read from the Flash, User Signature Row, Calibration
Row and Fuses, and read and write the EEPROM.
The Boot Loader support provides a real Read-While-Write self-programming mechanism for
downloading and uploading program code by the device itself. This feature allows flexible appli-
cation software updates controlled by the device using a Boot Loader application that reside in
the Boot Loader Section in the Flash. The Boot Loader can use any available communication
interface and associated protocol to read code and write (program) that code into the Flash
memory, or read out the program memory code. It has the capability to write into the entire
Flash, including the Boot Loader Section. The Boot Loader can thus modify itself, and it can also
erase itself from the code if the feature is not needed anymore.
• Fill the EEPROM page buffer with the selected number of bytes.
• Perform a EEPROM Page Erase.
• Perform a EEPROM Page Write.
• Fill the EEPROM page buffer with the selected number of bytes.
• Perform an EEPROM Page Erase and Write.
CC
voltage is below the minimum operating voltage for the device, the
for details on the available Lock Bit settings
XMEGA D
”LOCKBITS -
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