ATxmega256A3U Atmel Corporation, ATxmega256A3U Datasheet - Page 26

• Manufacturer Part Number: ATxmega256A3U
• Manufacturer: Atmel Corporation

Specifications of ATxmega256A3U

• 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 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): 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

14. Interrupts and Programmable Multi-level Interrupt Controller
14.1
14.2
14.3
Table 14-1.
8386A–AVR–07/11
Program Address
(Base Address)
Features
Overview
Interrupt vectors
0x000
0x002
0x004
Reset and Interrupt Vectors
Source
RESET
OSCF_INT_vect
PORTC_INT_base
•
•
•
•
Atmel
signal a change of state in peripherals, and this can be used to alter program execution. Periph-
erals can have one or more interrupts, and all are individually enabled and configured. When an
interrupt is enabled and configured, it will generate an interrupt request when the interrupt condi-
tion is present. The Programmable Multi-level Interrupt Controller (PMIC) controls the handling
and prioritizing of interrupt requests. When an interrupt request is acknowledged by the PMIC,
the program counter is set to point to the interrupt vector, and the interrupt handler can be
executed.
All peripherals can select between three different priority levels for their interrupts; low, medium
and high. Interrupts are prioritized according to their level and their interrupt vector address.
Medium level interrupts will interrupt low level interrupt handlers. High level interrupts will inter-
rupt both medium and low level interrupt handlers. Within each level, the interrupt priority is
decided from the interrupt vector address, where the lowest interrupt vector address has the
highest interrupt priority. Low level interrupts have an optional round-robin scheduling scheme to
ensure that all interrupts are serviced within a certain amount of time.
Non-Maskable Interrupts (NMI) is also supported and can be used for critical functions. If a boot-
loader is used, it is possible to move the interrupt vectors from the Application Section to the
Boot Loader Sections so interrupts can be used and executed also during self-programming.
The interrupt vector is the sum of the peripheral’s base interrupt address and the offset address
for specific interrupts in each peripheral. The base addresses for the XMEGA A3U devices are
shown in
described for each peripheral in the XMEGA AU manual. For peripherals or modules that have
only one interrupt, the interrupt vector is shown in
address.
Short and predictable interrupt response time
Separate interrupt configuration and vector address for each interrupt
Programmable Multi-level Interrupt Controller
Interrupt vectors can be moved from the Application Section to the Boot Loader Section
– Interrupt prioritizing according to level and vector address
– 3 selectable interrupt levels for all interrupts: Low, Medium and High
– Selectable round-robin priority scheme within low level interrupts
– Non-Maskable Interrupts for critical functions
®
AVR
Table
®
XMEGA
14-1. Offset addresses for each interrupt available in the peripheral are
®
have a Programmable Multi-level Interrupt Controller (PMIC). Interrupts
Interrupt Description
Crystal Oscillator Failure Interrupt vector (NMI)
Port C Interrupt base
Table
14-1. The program address is the word
XMEGA A3U
26