Datasheet

13. Interrupts
13.1. Overview
This section describes the specifics of the interrupt handling of the device. For a general explanation of
the AVR interrupt handling, refer to the description of Reset and Interrupt Handling.
In general:
• Each Interrupt Vector occupies two instruction words.
• The Reset Vector is affected by the BOOTRST fuse, and the Interrupt Vector start address is
affected by the IVSEL bit in MCUCR (MCUCR.IVSEL)
Related Links
Reset and Interrupt Handling on page 26
13.2. Interrupt Vectors in ATmega644A
Table 13-1. Reset and Interrupt Vectors in ATmega644A
Vector No
Program Address
(2)
Source Interrupts definition
1 0x0000
(1)
RESET External Pin, Power-on Reset, Brown-out Reset and Watchdog System
Reset
2 0x0002 INT0 External Interrupt Request 0
3 0x0004 INT1 External Interrupt Request 1
4 0x0006 INT2 External Interrupt Request 2
5 0x0008 PCINT0 Pin Change Interrupt Request 0
6 0x000A PCINT1 Pin Change Interrupt Request 1
7 0x000C PCINT2 Pin Change Interrupt Request 2
8 0x000E PCINT3 Pin Change Interrupt Request 3
9 0x0010 WDT Watchdog Time-out Interrupt
10 0x0012 TIMER2_COMPA Timer/Counter2 Compare Match A
11 0x0014 TIMER2_COMPB Timer/Coutner2 Compare Match B
12 0x0016 TIMER2_OVF Timer/Counter2 Overflow
13 0x0018 TIMER1_CAPT Timer/Counter1 Capture Event
14 0x001A TIMER1_COMPA Timer/Counter1 Compare Match A
15 0x001C TIMER1_COMPB Timer/Coutner1 Compare Match B
16 0x001E TIMER1_OVF Timer/Counter1 Overflow
17 0x0020 TIMER0_COMPA Timer/Counter0 Compare Match A
18 0x0022 TIMER0_COMPB Timer/Coutner0 Compare Match B
19 0x0024 TIMER0_OVF Timer/Counter0 Overflow
20 0x0026 SPI_STC SPI Serial Transfer Complete
Atmel ATmega644A [DATASHEET]
Atmel-42716C-ATmega644A_Datasheet_Complete-10/2016
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