Hitachi H8/3937 Series Hardware Manual page 113

Bit 3: Direct transfer on flag (DTON)
This bit designates whether or not to make direct transitions among active (high-speed), active
(medium-speed) and subactive mode when a SLEEP instruction is executed. The mode to which
the transition is made after the SLEEP instruction is executed depends on a combination of this
and other control bits.
Bit 3
DTON Description
•
0
When a SLEEP instruction is executed in active mode, a transition
is made to standby mode, watch mode, or sleep mode
•
When a SLEEP instruction is executed in subactive mode, a transition is made to
watch mode or subsleep mode
•
1
When a SLEEP instruction is executed in active (high-speed) mode, a direct
transition is made to active (medium-speed) mode if SSBY = 0, MSON = 1, and
LSON = 0, or to subactive mode if SSBY = 1, TMA3 = 1, and LSON = 1
•
When a SLEEP instruction is executed in active (medium-speed) mode, a direct
transition is made to active (high-speed) mode if SSBY = 0, MSON = 0, and
LSON = 0, or to subactive mode if SSBY = 1, TMA3 = 1, and LSON = 1
•
When a SLEEP instruction is executed in subactive mode, a direct transition is
made to active (high-speed) mode if SSBY = 1, TMA3 = 1, LSON = 0, and MSON
= 0, or to active (medium-speed) mode if SSBY = 1, TMA3 = 1, LSON = 0, and
MSON = 1
Bit 2: Medium speed on flag (MSON)
After standby, watch, or sleep mode is cleared, this bit selects active (high-speed) or active
(medium-speed) mode.
Bit 2
MSON Description
0 Operation in active (high-speed) mode
1 Operation in active (medium-speed) mode
(initial value)
(initial value)
101