System Control Registers - Renesas H8 Series Hardware Manual

Section 5 Power-Down Modes
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
System control register 1
System control register 2
System Control Register 1 (SYSCR1)
Bit
SSBY
Initial value
Read/Write 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
•
•
1
•
Rev. 6.00 Sep 12, 2006 page 90 of 526
REJ09B0326-0600
Abbreviation
SYSCR1
SYSCR2
7 6 5
STS2 STS1
0 0 0
R/W R/W
When a SLEEP instruction is executed in active mode, a transition is made
to sleep mode
When a SLEEP instruction is executed in subactive mode, a transition is
made to subsleep mode
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
R/W Initial Value
R/W H'07
R/W H'E0
4 3
STS0 LSON
0 0
R/W R/W
Address
H'FFF0
H'FFF1
2 1 0

MA1 MA0
1 1 1

R/W R/W
(initial value)