Rainbow Electronics ATmega64L - Manual (Page 42)

42
ATmega16(L)
2466B–09/01
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 “Reset and
Interrupt Handling” on page 11.
Interrupt Vectors in
ATmega16
Notes: 1. When the BOOTRST fuse is programmed, the device will jump to the Boot Loader
address at reset, see “Boot Loader Support – Read-While-Write Self-Programming”
on page 240.
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.
Table 19 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 loca-
tions. 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.
Table 18. Reset and Interrupt Vectors
Vector No.
Program
Address (2) Source Interrupt Definition
1 $000 (1) RESET External Pin, Power-on Reset, Brown-out
Reset, Watchdog Reset, and JTAG AVR
Reset
2 $002 INT0 External Interrupt Request 0
3 $004 INT1 External Interrupt Request 1
4 $006 TIMER2 COMP Timer/Counter2 Compare Match
5 $008 TIMER2 OVF Timer/Counter2 Overflow
6 $00A TIMER1 CAPT Timer/Counter1 Capture Event
7 $00C TIMER1 COMPA Timer/Counter1 Compare Match A
8 $00E TIMER1 COMPB Timer/Counter1 Compare Match B
9 $010 TIMER1 OVF Timer/Counter1 Overflow
10 $012 TIMER0 OVF Timer/Counter0 Overflow
11 $014 SPI, STC Serial Transfer Complete
12 $016 USART, RXC USART, Rx Complete
13 $018 USART, UDRE USART Data Register Empty
14 $01A USART, TXC USART, Tx Complete
15 $01C ADC ADC Conversion Complete
16 $01E EE_RDY EEPROM Ready
17 $020 ANA_COMP Analog Comparator
18 $022 TWI 2-wire Serial Interface
19 $024 INT2 External Interrupt Request 2
20 $026 TIMER0 COMP Timer/Counter0 Compare Match
21 $028 SPM_RDY Store Program Memory Ready