ATxmega64A4U Atmel Corporation, ATxmega64A4U Datasheet - Page 213

• Manufacturer Part Number: ATxmega64A4U
• Manufacturer: Atmel Corporation

Specifications of ATxmega64A4U

• Flash (kbytes): 64 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 32 MHz
• Cpu: 8-bit AVR
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 34
• Ext Interrupts: 34
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 2
• 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): 4
• 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: 5
• Output Compare Channels: 16
• Input Capture Channels: 16
• Pwm Channels: 16
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

17. Hi-Res - High-Resolution Extension
17.1
17.2
8331A–AVR–07/11
Features
Overview
•
•
•
The high-resolution (hi-res) extension can be used to increase the resolution of the waveform
generation output from a timer/counter by four or eight. It can be used for a timer/counter doing
frequency, single-slope PWM, or dual-slope PWM generation. It can also be used with the
AWeX if this is used for the same timer/counter.
The hi-res extension uses the peripheral 4x clock (Clk
be configured so the peripheral 4x clock frequency is four times higher than the peripheral and
CPU clock frequency when the hi-res extension is enabled. Refer to
and Prescalers” on page 85
Figure 17-1. Timer/counter operation with hi-res extension enabled.
When the hi-res extension is enabled, the timer/counter must run from a non-prescaled periph-
eral clock. The timer/counter counter will ignore its two least-significant bits (lsb) and count by
four for each peripheral clock cycle. Overflow/underflow and compare match of the 14 most-sig-
nificant bits (msb) is done in the timer/counter. Count and compare of the two lsb is handled and
compared in the hi-res extension running from the peripheral 4x clock.
The two lsb of the timer/counter period register must be set to zero to ensure correct operation.
If the count register is read from the application code, the two lsb will always be read as zero,
since the timer/counter run from the peripheral clock. The two lsb are also ignored when gener-
ating events.
When the hi-res plus feature is enabled, the function is the same as with the hi-res extension,
but the resolution will increase by eight instead of four. This also means that the 3 lsb are han-
dled by the hi-res extension instead of 2 lsb, as when only hi-res is enabled. The extra resolution
is achieved by counting on both edges of the peripheral 4x clock.
Increases waveform generator resolution up to 8x (3 bits)
Supports frequency, single-slope PWM, and dual-slope PWM generation
Supports the AWeX when this is used for the same timer/counter
PER[15:2]
CCxBUF[15:0]
CNT[15:2]
CCx[15:2]
=
" match"
for more details.
[1:0]
BOTTOM
= 0
0
0
2
Time /Counter
Generation
Waveform
=
TOP
2
Atmel AVR XMEGA AU
AWeX
PER4
Dead - Time
Insertion
). The system clock prescalers must
clk
PER
Generation
Protection
Pattern
”System Clock Selection
Fault
2
clk
HiRes
PER4
Pxn
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