AT32UC3B1256 Atmel Corporation, AT32UC3B1256 Datasheet - Page 72

• Manufacturer Part Number: AT32UC3B1256
• Manufacturer: Atmel Corporation

Specifications of AT32UC3B1256

• Flash (kbytes): 256 Kbytes
• Pin Count: 48
• Max. Operating Frequency: 60 MHz
• Cpu: 32-bit AVR
• # Of Touch Channels: 32
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 28
• Ext Interrupts: 28
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 3
• Twi (i2c): 1
• Uart: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 6
• Adc Resolution (bits): 10
• Adc Speed (ksps): 384
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 32
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 3.0-3.6 or (1.65-1.95+3.0-3.6)
• Operating Voltage (vcc): 3.0-3.6 or (1.65-1.95+3.0-3.6)
• Fpu: No
• Mpu / Mmu: Yes / No
• Timers: 10
• Output Compare Channels: 16
• Input Capture Channels: 6
• Pwm Channels: 13
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

10. Real Time Counter (RTC)
10.1
10.2
10.3
Figure 10-1. Real Time Counter Block Diagram
10.4
32059L–AVR32–01/2012
Features
Overview
Block Diagram
Product Dependencies
CLK_32
RCSYS
CLK32
1
0
CTRL
Rev: 2.3.1.1
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The Real Time Counter (RTC) enables periodic interrupts at long intervals, or accurate mea-
surement of real-time sequences. The RTC is fed from a 16-bit prescaler, which is clocked from
the system RC oscillator or the 32KHz crystal oscillator. Any tapping of the prescaler can be
selected as clock source for the RTC, enabling both high resolution and long timeouts. The pres-
caler cannot be written directly, but can be cleared by the user.
The RTC can generate an interrupt when the counter wraps around the value stored in the top
register (TOP), producing accurate periodic interrupts.
In order to use this module, other parts of the system must be configured correctly, as described
below.
32-bit real-time counter with 16-bit prescaler
Clocked from RC oscillator or 32KHz oscillator
Long delays
High resolution: Max count frequency 16KHz
Extremely low power consumption
Available in all sleep modes except Static
Interrupt on wrap
16-bit Prescaler
EN
– Max timeout 272years
PSEL
32-bit counter
TOP
VAL
TOPI
IRQ
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