HD6413008F RENESAS [Renesas Technology Corp], HD6413008F Datasheet - Page 511

• Manufacturer Part Number: HD6413008F
• Description: Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series
• Manufacturer: RENESAS [Renesas Technology Corp]

18.4.4
Figure 18.1 shows an example in which software standby mode is entered at the fall of NMI and
exited at the rise of NMI.
With the NMI edge select bit (NMIEG) cleared to 0 in SYSCR (selecting the falling edge), an
NMI interrupt occurs. Next the NMIEG bit is set to 1 (selecting the rising edge) and the SSBY bit
is set to 1; then the SLEEP instruction is executed to enter software standby mode.
Software standby mode is exited at the next rising edge of the NMI signal.
18.4.5
The I/O ports retain their existing states in software standby mode. If a port is in the high output
state, its output current is not reduced.
Clock
oscillator
φ
NMI
NMIEG
SSBY
Sample Application of Software Standby Mode
Note
Figure 18.1 NMI Timing for Software Standby Mode (Example)
NMI interrupt
handler
NMIEG = 1
SSBY = 1
SLEEP
instruction
Software standby
mode (power-
down state)
Rev.4.00 Aug. 20, 2007 Page 467 of 638
Oscillator
settling time
(t
osc2
)
18. Power-Down State
NMI exception
handling
REJ09B0395-0400