ATxmega16A4U Atmel Corporation, ATxmega16A4U Datasheet - Page 124

• 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

10.6.2
10.6.3
8331A–AVR–07/11
STATUS: Status Register
BACKUP0: Backup Register 0
This bit is protected by the Configuration Change Protection mechanism. For a detailed descrip-
tion, refer to
• Bit 7 – BBPWR: Battery Backup Power
This flag is set if no power is detected on the V
can be cleared by writing a one to this bit location.
• Bit 6:4 – Reserved
These bits are unused and reserved for future use. For compatibility with future devices, always
write these bits to zero when this register is written.
• Bit 3 – XOSCRDY: Crystal Oscillator Ready
This flag is set when the 32.678kHz crystal oscillator has started and is stable and ready. The
flag can be cleared by applying a reset to the battery backup system. The actual start-up time is
crystal dependent. Refer to the datasheet for the crystal oscillator used for more information.
• Bit 2 – XOSCFAIL: Crystal Oscillator Failure
This flag is set if a crystal oscillator failure is detected. The flag can be cleared by writing a one
to this bit location or by applying a reset to the battery backup system.
• Bit 1 – BBBODF: Battery Backup Brown-out Detection Flag
This flag is set if battery backup BOD is detected when the battery backup system is powered
from the V
valid when BBPWR is set.
• Bit 0 – BBPODF: Battery Backup Power-on Detection Flag
This flag is set if battery backup power-on is detected; i.e., when power is connected to the V
pin. The flag is updated only during device startup when main power is applied. Applying or
reapplying power to the V
power is removed and re-applied. The flag can be cleared by writing a one to this bit location.
This flag is not valid when BBPWR is set.
Bit
+0x01
Read/Write
Initial Value
Bit
+0x02
Read/Write
Initial Value
BAT
”Configuration Change Protection” on page
BBPWR
R/W
pin. The flag can be cleared by writing a one to this bit location. This flag is not
R/W
7
x
7
0
R/W
6
x
R
6
0
–
BAT
pin while main power is present will not change this flag until main
R/W
R
5
–
0
5
x
R
4
0
–
R/W
4
x
BACKUP0[7:0]
XOSCRDY
R/W
BAT
R/W
3
x
3
x
Atmel AVR XMEGA AU
pin when the device leaves reset. The flag
XOSCFAIL
12.
R/W
R/W
2
x
2
x
R/W
1
x
BBBODF
R/W
1
0
R/W
0
x
BBPODF
R/W
0
0
BACKUP0
STATUS
124
BAT