3.3.1 Interrupt Vectors in ATmega328P Automotive

A clarification for the source names of the Interrupt vectors has been made to comply with the header file naming convention.

Table 11-1. Reset and Interrupt Vectors in ATmega328P Automotive


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	PCINT0	Pin Change Interrupt Request 0
5	0x0008	PCINT1	Pin Change Interrupt Request 1
6	0x000A	PCINT2	Pin Change Interrupt Request 2
7	0x000C	WDT	Watchdog Time-out Interrupt
8	0x000E	TIMER2_COMPA	Timer/Counter2 Compare Match A
9	0x0010	TIMER2_COMPB	Timer/Coutner2 Compare Match B
10	0x0012	TIMER2_OVF	Timer/Counter2 Overflow
11	0x0014	TIMER1_CAPT	Timer/Counter1 Capture Event
12	0x0016	TIMER1_COMPA	Timer/Counter1 Compare Match A
13	0x0018	TIMER1_COMPB	Timer/Coutner1 Compare Match B
14	0x001A	TIMER1_OVF	Timer/Counter1 Overflow
15	0x001C	TIMER0_COMPA	Timer/Counter0 Compare Match A
16	0x001E	TIMER0_COMPB	Timer/Coutner0 Compare Match B
17	0x0020	TIMER0_OVF	Timer/Counter0 Overflow
18	0x0022	SPI_STC	SPI Serial Transfer Complete
19	0x0024	USART_RX	USART Rx complete
20	0x0026	USART_UDRE	USART Data Register Empty
21	0x0028	USART_TX	USART Tx complete
22	0x002A	ADC	ADC Conversion complete
23	0x002C	EE_READY	EEPROM Ready
24	0x002E	ANALOG_COMP	Analog Comparator
25	0x0030	TWI	Two-wire Serial Interface (I²C)
26	0x0032	SPM_READY	Store Program Memory Ready

Note:

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”.
When setting the IVSEL bit in MCUCR, 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.

The most typical and general program setup for the Reset and Interrupt Vector Addresses for ATmega328P Automotive is:

Address   Labels    Code                         Comments
0x0000               jmp      RESET               ; Reset
0x0001               jmp      INT0                ; IRQ0
0x0002               jmp      INT1                ; IRQ1
0x0003               jmp      PCINT0              ; PCINT0
0x0004               jmp      PCINT1              ; PCINT1
0x0005               jmp      PCINT2              ; PCINT2
0x0006               jmp      WDT                 ; Watchdog Timeout
0x0007               jmp      TIMER2_COMPA        ; Timer2 CompareA
0x0008               jmp      TIMER2_COMPB        ; Timer2 CompareB
0x0009               jmp      TIMER2_OVF          ; Timer2 Overflow
0x000A               jmp      TIMER1_CAPT         ; Timer1 Capture
0x000B               jmp      TIMER1_COMPA        ; Timer1 CompareA
0x000C               jmp      TIMER1_COMPB        ; Timer1 CompareB
0x000C               jmp      TIMER1_OVF          ; Timer1 Overflow
0x000E               jmp      TIMER0_COMPA        ; Timer0 CompareA
0x000F               jmp      TIMER0_COMPB        ; Timer0 CompareB
0x0010               jmp      TIMER0_OVF          ; Timer0 Overflow
0x0011               jmp      SPI_STC             ; SPI Transfer Complete
0x0012               jmp      USART_RXC           ; USART RX Complete
0x0013               jmp      USART_UDRE          ; USART UDR Empty
0x0014               jmp      USART_TXC           ; USART TX Complete
0x0015               jmp      ADC                 ; ADC Conversion Complete
0x0016               jmp      EE_READY            ; EEPROM Ready
0x0017               jmp      ANA_COMP            ; Analog Comparator
0x0018               jmp      TWI                 ; 2-wire Serial
0x0019               jmp      SPM_READY           ; SPM Ready
;
0x001A    RESET:     ldi      r16,high(RAMEND)    ; Main program start     
0x001B               out      SPH,r16             ; Set Stack Pointer to top of RAM
0x001C               ldi      r16,low(RAMEND)
0x001D               out      SPL,r16
0x001E               sei                          ; Enable interrupts
0x001F               <instr>  xxx
...       ...        ...                             ...