ATxmega128B1 Atmel Corporation, ATxmega128B1 Datasheet - Page 158

• 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

13.7.1
13.7.2
8291A–AVR–10/11
Input Capture
Frequency Capture
Figure 13-10. Event source selection for capture operation.
The event action setting in the timer/counter will determine the type of capture that is done.
The CC channels must be enabled individually before capture can be done. When the capture
condition occur, the timer/counter will time-stamp the event by copying the current CNT value in
the count register into the enabled CC channel register.
When an I/O pin is used as an event source for the capture, the pin must be configured for edge
sensing. For details on sense configuration on I/O pins, refer to
page
stored in the most-significant bit (msb) of the capture register. If the msb of the capture register
is zero, a falling edge generated the capture. If the msb is one, a rising edge generated the
capture.
Selecting the input capture event action makes the enabled capture channel perform an input
capture on an event. The interrupt flags will be set and indicate that there is a valid capture result
in the corresponding CC register. At the same time, the buffer valid flags indicate valid data in
the buffer registers.
The counter will continuously count from BOTTOM to TOP, and then restart at BOTTOM, as
shown in
Figure 13-11. Input capture timing.
Selecting the frequency capture event action makes the enabled capture channel perform an
input capture and restart on positive edge events. This enables the timer/counter to measure the
period or frequency of a signal directly. The capture result will be the time (T) from the previous
CNT
Event System
133. If the period register value is lower than 0x8000, the polarity of the I/O pin edge will be
Figure
CH0MUX
CH1MUX
CH3MUX
BOTTOM
events
TOP
13-11. The figure also shows four capture events for one capture channel.
Capture 0
Event channel 3
Event channel 0
Event channel 1
Capture 1
Capture 2
Rotate
Atmel AVR XMEGA B
”Input Sense Configuration” on
Event Source Selection
Capture 3
CCA capture
CCB capture
CCC capture
CCD capture
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