HD6417705 Datasheet, PDF (347/739 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7700 Series

Notes: 1. Only when the RTC is being used can standby mode be canceled using IRQ, IRL,
PINT, or RTC.
2. Use a power-on reset to cancel software standby mode.
WTCNT value
H'FF
Interrupt
request
Crystal oscillator settling
time and PLL synchronization
time
WDT overflow and branch to
interrupt handling routine
Clear the STBY bit in STBCR before
WTCNT reaches H'80. When the
STBY bit in STBCR is cleared, WTCNT
halts automatically.
H'80
Time
Figure 11.1 Canceling Standby Mode with STBY Bit in STBCR
Canceling with a Reset: Software standby mode is canceled by a reset (power-on or manual).
Keep the RESETP or RESETM pins low until the clock oscillation settles. The internal clock will
continue to be output to the CKIO pin.
11.6 Module Standby Function
11.6.1 Transition to Module Standby Function
Setting the standby control register MSTP bits to 1 halts the supply of clocks to the corresponding
on-chip peripheral modules. This function can be used to reduce the power consumption in the
normal mode and sleep mode. Before making a transition to module standby state, be sure to
disable the relevant module.
In module standby state, the functions of the external pins of the on-chip peripheral modules
change depending on the on-chip peripheral module and port settings. With a few exceptions, all
registers hold their values prior to halt.
Rev. 2.00, 09/03, page 301 of 690