ATmega16(L)
Interrupts
This section describes the specifics of the interrupt handling as performed in ATmega16. For a
general explanation of the AVR interrupt handling, refer to
Interrupt Vectors
in ATmega16
Table 18.
Reset and Interrupt Vectors
Vector No.
1
Program
Address
$000
Source
RESET
Interrupt Definition
External Pin, Power-on Reset, Brown-out
Reset, Watchdog Reset, and JTAG AVR
Reset
External Interrupt Request 0
External Interrupt Request 1
Timer/Counter2 Compare Match
Timer/Counter2 Overflow
Timer/Counter1 Capture Event
Timer/Counter1 Compare Match A
Timer/Counter1 Compare Match B
Timer/Counter1 Overflow
Timer/Counter0 Overflow
Serial Transfer Complete
USART, Rx Complete
USART Data Register Empty
USART, Tx Complete
ADC Conversion Complete
EEPROM Ready
Analog Comparator
Two-wire Serial Interface
External Interrupt Request 2
Timer/Counter0 Compare Match
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
$002
$004
$006
$008
$00A
$00C
$00E
$010
$012
$014
$016
$018
$01A
$01C
$01E
$020
$022
$024
$026
INT0
INT1
TIMER2 COMP
TIMER2 OVF
TIMER1 CAPT
TIMER1 COMPA
TIMER1 COMPB
TIMER1 OVF
TIMER0 OVF
SPI, STC
USART, RXC
USART, UDRE
USART, TXC
ADC
EE_RDY
ANA_COMP
TWI
INT2
TIMER0 COMP
21
$028
SPM_RDY
Store Program Memory Ready
Notes: 1. When the BOOTRST Fuse is programmed, the device will jump to the Boot Loader address at
reset, see
2. When the IVSEL bit in GICR is set, interrupt vectors will be moved to the start of the Boot
Flash section. The address of each Interrupt Vector will then be the address in this table added
to the start address of the Boot Flash section.
shows Reset and Interrupt Vectors placement for the various combinations of
BOOTRST and IVSEL settings. If the program never enables an interrupt source, the Interrupt
Vectors are not used, and regular program code can be placed at these locations. This is also
the case if the Reset Vector is in the Application section while the Interrupt Vectors are in the
Boot section or vice versa.
45
2466S–AVR–05/09
ATMEL [ ATMEL CORPORATION ]
