ATxmega128A1 Atmel Corporation, ATxmega128A1 Datasheet - Page 156

• Manufacturer Part Number: ATxmega128A1
• Manufacturer: Atmel Corporation

Specifications of ATxmega128A1

• 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: 78
• Ext Interrupts: 78
• Usb Speed: No
• Usb Interface: No
• Spi: 12
• Twi (i2c): 4
• Uart: 8
• 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
• Dac Channels: 4
• Dac Resolution (bits): 12
• Temp. Sensor: Yes
• Crypto Engine: AES/DES
• Sram (kbytes): 8
• Eeprom (bytes): 2048
• Self Program Memory: YES
• External Bus Interface: 1
• Dram Memory: sdram
• 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: 8
• Output Compare Channels: 24
• Input Capture Channels: 24
• Pwm Channels: 24
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

14.7
8077H–AVR–12/09
Capture Channel
Figure 14-7. Changing The Period without Buffering
When double buffering is used, the buffer can be written at any time, but the Period Register is
always updated on the “update” condition as shown in
and generation of odd waveforms.
Figure 14-8. Changing Period using Buffering
The CC channels can be used as capture channel to capture external events and give them a
time-stamp indicating time of occurrence. To use capture the Counter must be set in normal
operation.
Events are used to trigger the capture, i.e any events from the Event System including pin
change from any pin can trigger a capture operation. The Event Source Select setting, selects
the event channel that will trigger CC channel A, and the following event channels will then trig-
ger events on the following CC channels if configured. For instance setting the Event Source
Select to event channel 2 will result in CC channel A being connected to Event Channel 2, CC
channel B to event channel 3 and so on.
CNT
CNT
MAX
BOT
MAX
BOT
PERBUF that is higher
New Period written to
than current CNT
New TOP written to
PER that is higher
than current CNT
New Period written to
PERBUF that is lower
than current CNT
Counter Wraparound
New TOP written to
PER that is lower
than current CNT
Figure
14-8. This prevents wraparound
New PER is updated
with PERBUF value.
XMEGA A
"update"
"write"
"update"
"write"
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