Mode Transitions And Lsi States - Renesas H8S/2100 Series Hardware Manual

Section 26 Power-Down Modes
26.2

Mode Transitions and LSI States

Figure 26.1 shows the possible mode transition diagram. The mode transition from program
execution state to program halt state is performed by the SLEEP instruction. The mode transition
from program halt state to program execution state is performed by an interrupt. The RES input
causes a mode transition from any state to the reset state. Table 26.3 shows the LSI internal states
in each operating mode.
Program execution state
SCK2 to
SCK0 = 0
Notes: When a transition is made between modes by means of an interrupt, the transition cannot be made
on interrupt source generation alone. Ensure that interrupt handling is performed after accepting the
interrupt request.
1. NMI, IRQ0 to IRQ15, KIN0 to KIN15, WUE8 to WUE15, and WDT_1, PS2 and CIR interrupts
2.
NMI, IRQ0 to IRQ15, KIN0 to KIN15, WUE8 to WUE15, and PS2 interrupts
Rev. 1.00 Apr. 28, 2008 Page 848 of 994
REJ09B0452-0100
Reset state
RES pin = High
High-speed
mode
(main clock)
SCK2 to
SCK0 ≠ 0
Medium-speed
mode
: Transition after exception processing
Figure 26.1 Mode Transition Diagram
RES pin = Low
SLEEP instruction
Any interrupt
SLEEP instruction
2
External interrupt*
SLEEP
instruction
1
Interrupt*
LSON bit = 0
Program halt state
SSBY = 0, LSON = 0
Sleep mode
(main clock)
SSBY = 1,
PSS = 0, LSON = 0
Software
standby mode
SSBY = 1,
PSS = 1, DTON = 0
Watch mode
(subclock)
: Power-down mode