Atmel AT90S2333-8AC, Manual

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AT90S/LS2333 and AT90S/LS4433
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instruction, and it is incremented by two when an address is popped from the Stack with return from subroutine RET or
return from interrupt RETI.
Reset and Interrupt Handling
The AT90S2333/4433 provides 13 different interrupt sources. These interrupts and the separate reset vector, each have a
separate program vector in the program memory space. All interrupts are assigned individual enable bits which 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 3. The list also determines the priority levels of the different interrupts. The lower
the address the higher is the priority level. RESET has the highest priority, and next is INT0 - the External Interrupt Request
0, etc.
The most typical 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 TIM1_CAPT ; Timer1 Capture Handler
$004 rjmp TIM1_COMP ; Timer1 compare Handler
$005 rjmp TIM1_OVF ; Timer1 Overflow Handler
$006 rjmp TIM0_OVF ; Timer0 Overflow Handler
$007 rjmp SPI_STC; ; SPI Transfer Complete Handler
$008 rjmp UART_RXC ; UART RX Complete Handler
$009 rjmp UART_DRE ; UDR Empty Handler
$00a rjmp UART_TXC ; UART TX Complete Handler
$00b rjmp ADC ; ADC Conversion Complete Interrupt Handler
$00c rjmp EE_RDY ; EEPROM Ready Handler
$00d rjmp ANA_COMP ; Analog Comparator Handler
;
Table 3. Reset and Interrupt Vectors
Vector No. Program Address Source Interrupt Definition
1 $000 RESET External Pin, Power-On Reset, Brown-Out Reset and Watchdog Reset.
2 $001 INT0 External Interrupt Request 0
3 $002 INT1 External Interrupt Request 1
4 $003 TIMER1 CAPT Timer/Counter1 Capture Event
5 $004 TIMER1 COMP Timer/Counter1 Compare Match
6 $005 TIMER1 OVF Timer/Counter1 Overflow
7 $006 TIMER0 OVF Timer/Counter0 Overflow
8 $007 SPI, STC Serial Transfer Complete
9 $008 UART, RX UART, Rx Complete
10 $009 UART, UDRE UART Data Register Empty
11 $00A UART, TX UART, Tx Complete
12 $00B ADC ADC Conversion Complete
13 $00C EE_RDY EEPROM Ready
14 $00D ANA_COMP Analog Comparator