H8SXSLASH1663M datasheet(1292/1504 Pages) RENESAS

1292 / 1504 page

Section 28 Power-Down Modes

Rev. 2.00 Sep. 24, 2008 Page 1260 of 1468

REJ09B0412-0200

28.4

Module Stop State

Module stop functionality can be set for individual on-chip peripheral modules.

When the corresponding MSTP bit in MSTPCRA, MSTPCRB, or MSTPCRC is set to 1, module

operation stops at the end of the bus cycle and a transition is made to a module stop state. The

CPU continues operating independently.

When the corresponding MSTP bit is cleared to 0, a module stop state is cleared and the module

starts operating at the end of the bus cycle. In a module stop state, the internal states of modules

other than the SCI are retained.

After the reset state is cleared, all modules other than the EXDMAC, DMAC, and DTC and on-

chip RAM are placed in a module stop state.

The registers of the module for which the module stop state is selected cannot be read from or

written to.

28.5

Sleep Mode

28.5.1

Entry to Sleep Mode

When the SLEEP instruction is executed when the SSBY bit in SBYCR is 0, the CPU enters sleep

mode. In sleep mode, CPU operation stops but the contents of the CPU's internal registers are

retained. Other peripheral functions do not stop.

28.5.2

Exit from Sleep Mode

Sleep mode is exited by any interrupt, signals on the

RES or STBY pin, and a reset caused by a

watchdog timer overflow, a voltage monitoring reset*, or a power-on reset*.

• Exit from sleep mode by interrupt

When an interrupt occurs, sleep mode is exited and interrupt exception processing starts. Sleep

mode is not exited if the interrupt is disabled, or interrupts other than NMI are masked by the

CPU.

• Exit from sleep mode by RES pin

Setting the

RES pin level low selects the reset state. After the stipulated reset input duration,

driving the

RES pin high makes the CPU start the reset exception processing.

• Exit from sleep mode by STBY pin

When the

STBY pin level is driven low, a transition is made to hardware standby mode.

H8SX/1663M Datasheet(PDF) 1292 Page - Renesas Technology Corp