ATxmega64A3U Atmel Corporation, ATxmega64A3U Datasheet - Page 143

• Manufacturer Part Number: ATxmega64A3U
• Manufacturer: Atmel Corporation

Specifications of ATxmega64A3U

• 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 Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 10
• Twi (i2c): 2
• Uart: 7
• 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: 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: 7
• Output Compare Channels: 22
• Input Capture Channels: 22
• Pwm Channels: 22
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

13.3.4
13.4
8331A–AVR–07/11
Reading the Pin Value
Wired-AND
Figure 13-6. Output configuration - Wired-OR with optional pull-down.
In the wired-AND configuration, the pin will be driven low when the corresponding bits in the
OUT and DIR registers are written to zero. When the OUT register is set to one, the pin is
released allowing the pin to be pulled high with the internal or an external pull-resistor. If internal
pull-up is used, this is also active if the pin is set as input.
Figure 13-7. Output configuration - Wired-AND with optional pull-up.
Independent of the pin data direction, the pin value can be read from the IN register, as shown in
Figure 13-1 on page
register bit and the preceding flip-flop constitute a synchronizer. The synchronizer introduces a
delay on the internal signal line.
chronization when reading an externally applied pin value. The maximum and minimum
propagation delays are denoted as t
140. If the digital input is disabled, the pin value cannot be read. The IN
OUTn
OUTn
INn
INn
Figure 13-8 on page 144
pd,max
and t
pd,min
, respectively.
Atmel AVR XMEGA AU
shows a timing diagram of the syn-
Pn
Pn
143