HD6473637SW datasheet(60/418 Pages) RENESAS

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Reset state

Program halt state

Exception-handling state

Program execution state

Reset cleared

SLEEP instruction executed

Reset

occurs

Interrupt

source

Reset

occurs

Exception-

handling

request

Exception-

handling

complete

Reset occurs

Figure 2.15 State Transitions

2.7.2

Program Execution State

In the program execution state the CPU executes program instructions in sequence.

There are three modes in this state, two active modes (high speed and medium speed) and one

subactive mode. Operation is synchronized with the system clock in active mode (high speed and

medium speed), and with the subclock in subactive mode. See section 5, Power-Down Modes for

details on these modes.

2.7.3

Program Halt State

In the program halt state there are four modes: sleep mode, standby mode, watch mode, and

subsleep mode. See section 5, Power-Down Modes for details on these modes.

2.7.4

Exception-Handling State

The exception-handling state is a transient state occurring when exception handling is started by a

reset or interrupt and the CPU changes its normal processing flow. In exception handling caused

by an interrupt, SP (R7) is referenced and the PC and CCR values are saved on the stack.

For details on interrupt handling, see 3.3, Interrupts.

HD6473637SW Datasheet(PDF) 60 Page - Renesas Technology Corp