SH7011 Datasheet, PDF (46/292 Pages) Renesas Technology Corp – CMOS single-chip microprocessors

2.5 Processing States
2.5.1 State Transitions
The CPU has four processing states: reset, exception processing, program execution and power-
down. Figure 2.6 shows the transitions between the states.
From only state
when RES = 0
Power-on reset state
Reset states
Interrupt
source
occurs
RES = 1
Exception
processing state
Exception
processing
source occurs
Exception
processing
ends
Program execution state
Sleep
instruction
Sleep mode
Power-down state
Figure 2.6 Transitions between Processing States
Reset State: The CPU resets in the reset state. When the RES pin level goes low, a power-on reset
results.
Exception Processing State: The exception processing state is a transient state that occurs when
exception processing sources such as resets or interrupts alter the CPU’s processing state flow.
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