HD64F3642AHV Datasheet, PDF (112/551 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

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
Abbreviation
SYSCR1
SYSCR2
R/W
R/W
R/W
Initial Value
H'07
H'E0
Address
H'FFF0
H'FFF1
System Control Register 1 (SYSCR1)
Bit
Initial value
Read/Write
7
6
5
4
3
2
SSBY STS2 STS1 STS0 LSON

0
0
0
0
0
1
R/W
R/W
R/W
R/W
R/W

1
MA1
1
R/W
0
MA0
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
0
1
Description
• 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
(initial value)
• 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
Rev. 6.00 Sep 12, 2006 page 90 of 526
REJ09B0326-0600