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

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 reset input
causes a mode transition from any state to the reset state. For the details on the types of resets, see
section 4, Resets. 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, WUE0 to WUE15, WDT_1, and PS2 interrupts
2. NMI, IRQ0 to IRQ15, KIN0 to KIN15, WUE0 to WUE15, and PS2 interrupts
Reset state
Reset cancel
High-speed
mode
(main clock)
SCK2 to
SCK0 ≠ 0
Medium-speed
mode
: Transition after exception processing
Figure 26.1 Mode Transition Diagram
Reset input
RES pin = Low
SLEEP instruction
Any interrupt
SLEEP instruction
External
2
interrupt*
SLEEP
instruction
1
Interrupt*
LSON bit = 0
Rev. 1.00 May 09, 2008 Page 817 of 954
Section 26 Power-Down Modes
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
REJ09B0462-0100