ATxmega256A3 Atmel Corporation, ATxmega256A3 Datasheet - Page 14

• Manufacturer Part Number: ATxmega256A3
• Manufacturer: Atmel Corporation

Specifications of ATxmega256A3

• 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: 50
• Ext Interrupts: 50
• Usb Speed: No
• Usb Interface: No
• 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): 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

3.14.3
3.14.4
3.14.5
8077H–AVR–12/09
RAMPX - Extended X-Pointer Register
RAMPY - Extended Y-Pointer Register
RAMPZ - Extended Z-Pointer Register
data addresses below 64K bytes, this register is not in use. This register is not available if the
data memory including external memory is less than 64K bytes.
• Bit 7:0 – RAMPD[7:0]: Extended Direct Addressing bits
These bits holds the 8 MSB of the 24-bit address created by RAMPD and the 16-bit operand.
Only the number of bits required to address the available data memory is implemented for each
device. Unused bits will always read as zero.
This register is concatenated with the X-register for indirect addressing (LD/LDD/ST/STD) of the
whole data memory space on devices with more than 64K bytes of data memory. When access-
ing data addresses below 64K bytes, this register is not in use. This register is not available if the
data memory including external memory is less than 64K bytes.
• Bit 7:0 – RAMPX[7:0]: Extended X-pointer Address bits
These bits holds the 8 MSB of the 24-bit address created by RAMPX and the 16-bit X-register.
Only the number of bits required to address the available data memory is implemented for each
device. Unused bits will always read as zero.
This register is concatenated with the Y-register for indirect addressing (LD/LDD/ST/STD) of the
whole data memory space on devices with more than 64K bytes of data memory. When access-
ing data addresses below 64K bytes, this register is not in use. This register is not available if the
data memory including external memory is less than 64K bytes.
• Bit 7:0 – RAMPY[7:0]: Extended Y-pointer Address bits
These bits hold the 8 MSB of the 24-bit address created by RAMPY and the 16-bit Y-register.
Only the number of bits required to address the available data memory is implemented for each
device. Unused bits will always read as zero.
This register is concatenated with the Z-register for indirect addressing (LD/LDD/ST/STD) of the
whole data memory space on devices with more than 64K bytes of data memory. RAMPZ is
concatenated with the Z-register when reading (ELPM) program memory locations above the
Bit
+0x0A
Read/Write
Initial Value
Bit
+0x09
Read/Write
Initial Value
Bit
+0x08
Read/Write
Initial Value
R/W
R/W
R/W
7
0
7
0
7
0
R/W
R/W
R/W
6
0
6
0
6
0
R/W
R/W
R/W
5
0
5
0
5
0
R/W
R/W
R/W
4
0
4
0
4
0
RAMPD[7:0]
RAMPX[7:0]
RAMPY[7:0]
R/W
R/W
R/W
3
0
3
0
3
0
R/W
R/W
R/W
2
0
2
0
2
0
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
RAMPD
RAMPX
RAMPY
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