ATxmega256A3B Atmel Corporation, ATxmega256A3B Datasheet - Page 258

• Manufacturer Part Number: ATxmega256A3B
• Manufacturer: Atmel Corporation

Specifications of ATxmega256A3B

• Flash (kbytes): 256 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: 47
• Ext Interrupts: 49
• Usb Speed: No
• Usb Interface: No
• Spi: 8
• Twi (i2c): 2
• Uart: 6
• 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): 16
• Eeprom (bytes): 4096
• 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

22.3
22.3.1
22.3.2
22.3.3
8077H–AVR–12/09
Registers Description
TXPLCTRL - IRCOM Transmitter Pulse Length Control Register
RXPLCTRL - IRCOM Receiver Pulse Length Control Register
CTRL - IRCOM Control Register
• Bits 7:0 - TXPLCTRL[7:0] - Transmitter Pulse Length Control
The 8-bit value sets the pulse modulation scheme for the transmitter. Setting this register will
have no effect if IRCOM mode is not selected by a USART.
By leaving this register value to zero, 3/16 of baud rate period pulse modulation is used.
Setting this value from 1 to 254 will give a fixed pulse length coding. The 8-bit value sets the
number of system clock periods for the pulse. The start of the pulse will be synchronized with the
rising edge of the baud rate clock.
Setting the value to 255 (0xFF) will disable pulse coding, letting the RX and TX signals pass
through the IRCOM Module unaltered. This enables other features through the IRCOM Module,
such as half-duplex USART, Loop-back testing and USART RX input from an Event Channel.
Note:
• Bits 7:0 - RXPLCTRL[7:0] - Receiver Pulse Length Control
The 8-bit value sets the filter coefficient for the IRCOM transceiver. Setting this register will have
no effect if IRCOM mode is not selected by a USART.
By leaving this register value to zero, filtering is disabled. Setting this value between 1 and 255
will enable filtering, where x+1 equal samples is required for the pulse to be accepted.
Note:
• Bits 7:4 - Reserved
These bits are unused and reserved for future use. For compatibility with future devices, always
write these bits to zero when this register is written.
Bit
+0x01
Read/Write
Initial Value
Bit
+0x02
Read/Write
Initial Value
Bit
+0x00
Read/Write
Initial Value
TXPCTRL must be configured before USART transmitter is enabled (TXEN).
RXPCTRL must be configured before USART receiver is enabled (RXEN).
R/W
R/W
7
0
7
0
7
R
0
-
R/W
R/W
6
0
6
0
6
R
0
-
R/W
R/W
5
0
5
0
R
5
0
-
R/W
R/W
4
0
TXPLCTRL[7:0]
4
0
RXPLCTRL[7:0]
R
4
0
-
R/W
R/W
R/W
3
0
3
0
3
0
R/W
R/W
R/W
2
0
2
0
2
0
EVSEL[3:0]
R/W
R/W
R/W
1
0
1
0
1
0
XMEGA A
R/W
R/W
R/W
0
0
0
0
0
0
TXPLCTRL
RXPLCTRL
CTRL
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