Rainbow Electronics AT90S2313 - Manual (Page 18)

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AT90S2313
0839I–AVR–06/02
Reset and Interrupt
Handling The AT90S2313 provides 10 different interrupt sources. These interrupts and the sepa-
rate Reset Vector each have a separate Program Vector in the program memory space.
All the interrupts are assigned individual enable bits that must be set (one) together with
the I-bit in the Status Register in order to enable the interrupt.
The lowest addresses in the Program memory space are automatically defined as the
Reset and Interrupt Vectors. The complete list of vectors is shown in Table 2. The list
also determines the priority levels of the different interrupts. The lower the address, the
higher the priority level. RESET has the highest priority, and next is INT0 (the External
Interrupt Request 0), etc.
The most typical and general program setup for the Reset and Interrupt Vector
addresses are:
Address Labels Code Comments
$000 rjmp RESET ; Reset Handler
$001 rjmp EXT_INT0 ; IRQ0 Handler
$002 rjmp EXT_INT1 ; IRQ1 Handler
$003 rjmp TIM_CAPT1 ; Timer1 Capture Handler
$004 rjmp TIM_COMP1 ; Timer1 Compare Handler
$005 rjmp TIM_OVF1 ; Timer1 Overflow Handler
$006 rjmp TIM_OVF0 ; Timer0 Overflow Handler
$007 rjmp UART_RXC ; UART RX Complete Handler
$008 rjmp UART_DRE ; UDR Empty Handler
$009 rjmp UART_TXC ; UART TX Complete Handler
$00a rjmp ANA_COMP ; Analog Comparator Handler
;
$00b MAIN: ldi r16,low(RAMEND); Main program start
$00c out SPL,r16
$00d <instr> xxx
… … … …
Table 2. Reset and Interrupt Vectors
Vector No. Program Address Source Interrupt Definition
1 $000 RESET Hardware Pin, Power-on Reset and
Watchdog Reset
2 $001 INT0 External Interrupt Request 0
3 $002 INT1 External Interrupt Request 1
4 $003 TIMER1 CAPT1 Timer/Counter1 Capture Event
5 $004 TIMER1 COMP1 Timer/Counter1 Compare Match
6 $005 TIMER1 OVF1 Timer/Counter1 Overflow
7 $006 TIMER0 OVF0 Timer/Counter0 Overflow
8 $007 UART, RX UART, RX Complete
9 $008 UART, UDRE UART Data Register Empty
10 $009 UART, TX UART, TX Complete
11 $00A ANA_COMP Analog Comparator