ATxmega128B1 Atmel Corporation, ATxmega128B1 Datasheet - Page 204

• Manufacturer Part Number: ATxmega128B1
• Manufacturer: Atmel Corporation

Specifications of ATxmega128B1

• Flash (kbytes): 128 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: 53
• Ext Interrupts: 53
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 3
• Twi (i2c): 1
• Uart: 2
• Segment Lcd: 160
• 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
• Temp. Sensor: Yes
• Crypto Engine: AES/DES
• Sram (kbytes): 8
• Eeprom (bytes): 2048
• 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: 3
• Output Compare Channels: 10
• Input Capture Channels: 10
• Pwm Channels: 10
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

17.3
17.3.1
8291A–AVR–10/11
Register Descriptions
CTRL – Control register
• Bit 7:3 – 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 2:0 – PRESCALER[2:0]: Clock Prescaling factor
These bits define the prescaling factor for the RTC clock according to
Table 17-1.
Bit
+0x00
Read/Write
Initial Value
PRESCALER[2:0]
000
001
010
011
100
101
110
111
R
7
–
0
Real-time counter clock prescaling factor.
R
6
–
0
Group Configuration
5
–
R
0
DIV1024
DIV256
DIV16
DIV64
DIV1
DIV2
DIV8
OFF
4
–
R
0
R
3
–
0
Atmel AVR XMEGA B
RTC Clock Prescaling
No clock source, RTC stopped
RTC clock / 1 (no prescaling)
RTC clock / 2
RTC clock / 8
RTC clock / 16
RTC clock / 64
RTC clock / 256
RTC clock / 1024
R/W
2
0
PRESCALER[2:0]
Table 17-1 on page
R/W
1
0
R/W
0
0
CTRL
204.
204