Renesas H8 Series Hardware Manual

Section 5 Power-Down Modes
Rev. 7.00 Mar 10, 2005 page 122 of 652
REJ09B0042-0700
11. On the H8/38124 Group, operates only when the on-chip oscillator is selected; otherwise stops and stands by. On
the H8/38024, H8/38024S, and H8/38024R Group, stops and stands by.
5.1.1 System Control Registers
The operation mode is selected using the system control registers described in table 5.3.
Table 5.3 System Control Registers
Name Abbreviation R/W Initial Value Address
System control register 1 SYSCR1 R/W H'07 H'FFF0
System control register 2 SYSCR2 R/W H'F0 H'FFF1
System Control Register 1 (SYSCR1)
Bit
Initial value
Read/Write
7
SSBY
0
R/W
6
STS2
0
R/W
5
STS1
0
R/W
4
STS0
0
R/W
3
LSON
0
R/W
0
MA0
1
R/W
2

1

1
MA1
1
R/W
SYSCR1 is an 8-bit read/write register for control of the power-down modes.
Upon reset, SYSCR1 is initialized to H'07.
Bit 7—Software Standby (SSBY)
This bit designates transition to standby mode or watch mode.
Bit 7
SSBY Description
0
• When a SLEEP instruction is executed in active mode, (initial value)
a transition is made to sleep mode
• When a SLEEP instruction is executed in subactive mode, a transition is made to
subsleep mode
1
• When a SLEEP instruction is executed in active mode, a transition is made to
standby mode or watch mode
• When a SLEEP instruction is executed in subactive mode, a transition is made to
watch mode

Renesas H8 Series Specifications

General

Brand	Renesas
Model	H8 Series
Category	Computer Hardware
Language	English