ATxmega64D3 Atmel Corporation, ATxmega64D3 Datasheet - Page 49

• Manufacturer Part Number: ATxmega64D3
• Manufacturer: Atmel Corporation

Specifications of ATxmega64D3

• Flash (kbytes): 64 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 32 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 50
• Ext Interrupts: 50
• Usb Speed: No
• Usb Interface: No
• Spi: 5
• Twi (i2c): 2
• Uart: 3
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 16
• Adc Resolution (bits): 12
• Adc Speed (ksps): 200
• Analog Comparators: 2
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• 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: 18
• Input Capture Channels: 18
• Pwm Channels: 18
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

5.7.2
8210B–AVR–04/10
QDEC Setup
Figure 5-4
QDPH90 are the two quadrature signals. When QDPH90 leads QDPH0, the rotation is defined
as positive or forward. When QDPH0 leads QDPH90, the rotation is defined as negative, or
reverse. The concatenation of the two phase signals is called the quadrature state or the phase
state.
In order to know the absolute rotary displacement a third index signal (QDINDX) can be used.
This gives an indication once per revolution.
For a full QDEC setup the following is required:
The following procedure should be used for QDEC setup:
The angle of a quadrature encoder attached to QDPH0, QDPH90 (and QINDX) can now be read
directly from the Timer/Counter Count register. If the Count register is different from BOTTOM
when the index is recognized, the Timer/Counter error flag is set. Similarly the error flag is set if
the position counter passes BOTTOM without the recognition of the index.
• I/O port pins - quadrature signal input
• The Event System - quadrature decoding
• A Timer/Counter - up, down and optional index count
• Choose two successive pins on a port as QDEC phase inputs.
• Set pin direction for QDPH0 and QDPH90 as input.
• Set pin configuration for QDPH0 and QDPH90 to low level sense.
• Select QDPH0 pin as multiplexer input for an event channel, n.
• Enable quadrature decoding and digital filtering in the Event Channel.
• Optional:
• Set quadrature decoding as event action for a Timer/Counter.
• Select Event Channel n as event source the Timer/Counter.
• Set the period register of the Timer/Counter to ('line count' * 4 - 1). (The line count of the
• Enable the Timer/Counter by setting CLKSEL to a CLKSEL_DIV1.
quadrature encoder).
a. Setup QDEC index (QINDX).
b. Select a third pin for QINDX input.
c. Set pin direction for QINDX as input.
d. Set pin configuration for QINDX to sense both edges.
e. Select QINDX as multiplexer input for Event Channel n+1
f.
g. Select the Index Recognition mode for Event Channel n+1.
Set the Quadrature Index Enable bit in Event Channel n+1.
shows typical quadrature signals from a rotary encoder. The signals QDPH0 and
XMEGA D
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