RX610 Group
8. Low Power Consumption
R01UH0032EJ0120 Rev.1.20
Page 193 of 1006
Feb 20, 2013
8.5.3.2
Canceling Software Standby Mode
Software standby mode is canceled by an external interrupt (NMI or IRQ0 to IRQ15*
1
) or the reset signal from the RES#
pin.
1.
Canceling by an interrupt
When an NMI or IRQ0 to IRQ15*
1
interrupt request signal is input, clock oscillation starts, and stable clocks are
supplied to the entire LSI after the time selected by the STS[4:0] bits in SBYCR has passed, software standby mode
is canceled, and the interrupt exception handling is started.
To cancel software standby mode by an interrupt IRQ0 to IRQ15*
1
, set the corresponding enable bit (IENj bit in
IERm)*
2
to 1 and mask interrupts with a higher priority than interrupts IRQ0 to IRQ15*
1
.
To cancel software standby mode by an interrupt IRQ0 to IRQ15 for which edge detection is set, 0 should be written
to the status flag (the IR bit in IRn of the ICU) of the corresponding interrupt at the beginning of the exception
handler for the interrupt.
In addition, the interrupt status flag of an interrupt IRQ0 to IRQ15, which is not specified as a trigger for recovery,
might be set in software standby mode*
3
. Therefore, clear the IR flag after the recovery from software standby mode.
Notes: 1 An interrupt from among IRQ0 to IRQ15 cannot be used as a trigger for release from software standby mode
if the corresponding SSIj bit (j = 15 to 0) in SSIER of the ICU has been set to 0. For details, see section 10,
Interrupt Control Unit (ICU).
2 For details, see section 10, Interrupt Control Unit (ICU).
3. For details, see section 10.6.2, Return from Software Standby Mode.
2.
Canceling by the RES# pin
When the RES# pin is driven low, clock oscillation starts and at the same time the clocks are supplied to the entire
LSI. Be sure to hold the RES# pin low until the clock oscillation settles. When the RES# pin is driven high, the CPU
begins the reset exception handling.