State Program execution state
Exception-handling state
Bus-released state
Reset state
Power-down state
The CPU executes program instructions in sequence.
A transient state in which the CPU executes a hardware
sequence (saving the program counter and status register,
fetching a vector from the vector table, etc.) triggered by a reset,
interrupt, or other exception.
The state in which the CPU has released the external bus in
response to a bus request signal from an external device, and
is waiting for the bus to be returned.
The state in which the CPU and all on-chip supporting
modules have been initialized and are stopped.
A state in which some
or all of the clock
signals are stopped to
conserve power.
Sleep mode
Software standby mode
Hardware standby mode
Figure 3-11 Operating States
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