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32000D–04/2011
AVR32
The addresses of the interrupt routines are calculated by adding the address on the autovector
offset bus to the value of the Exception Vector Base Address (EVBA). The INT0, INT1, INT2,
INT3, and NMI signals indicate the priority of the pending interrupt. INT0 has the lowest priority,
and NMI the highest priority of the interrupts. Implementations may require that EVBA is aligned
in an IMPLEMENTATION DEFINED way in order to support autovectoring.
8.3.1
Description of events in AVR32A
8.3.1.1
Reset Exception
The Reset exception is generated when the reset input line to the CPU is asserted. The Reset
exception can not be masked by any bit. The Reset exception resets all synchronous elements
and registers in the CPU pipeline to their default value, and starts execution of instructions at
address 0x8000_0000.
SR = reset_value_of_SREG;
PC = 0x8000_0000;
All other system registers are reset to their reset value, which may or may not be defined. Refer
to the Programming Model chapter for details.
8.3.1.2
OCD Stop CPU Exception
The OCD Stop CPU exception is generated when the OCD Stop CPU input line to the CPU is
asserted. The OCD Stop CPU exception can not be masked by any bit. This exception is identi-
cal to a non-maskable, high priority breakpoint. Any subsequent operation is controlled by the
OCD hardware. The OCD hardware will take control over the CPU and start to feed instructions
directly into the pipeline.
RSR_DBG = SR;
RAR_DBG = PC;
SR[M2:M0] = B’110;
SR[R] = 0;
SR[J] = 0;
SR[D] = 1;
SR[DM] = 1;
SR[EM] = 1;
SR[GM] = 1;