Emulation Mode; Idle State - Analog Devices ADSP-BF53x Blackfin Reference

RTI ; /* Return from Reset Event */
WAIT_HERE :
JUMP WAIT_HERE ;
START: /* IVG15 vectors here */
[--SP] = RETI ;
to stack */

Emulation Mode

The processor enters Emulation mode if Emulation mode is enabled and
either of these conditions is met:
• An external emulation event occurs.
• The
EMUEXCPT
The processor remains in Emulation mode until the emulation service
routine executes an
instruction executes, the processor switches to User mode. Otherwise,
RTE
the processor switches to Supervisor mode to service the interrupt.
Emulation mode is the highest priority mode, and the processor
has unrestricted access to all system resources.

Idle State

Idle state stops all processor activity at the user's discretion, usually to
conserve power during lulls in activity. No processing occurs during the
Idle state. The Idle state is invoked by a sequential
instruction notifies the processor hardware that the Idle state is
IDLE
requested.
ADSP-BF53x/BF56x Blackfin Processor Programming Reference
/* Wait here till IVG15 interrupt is serviced */
/* Enables interrupts and saves return address
instruction is issued.
instruction. If no interrupts are pending when the
RTE
Operating Modes and States
instruction. The
IDLE
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