HD64F3694FXV Datasheet, PDF (105/452 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 6 Power-Down Modes
Section 6 Power-Down Modes
This LSI has six modes of operation after a reset. These include a normal active mode and four
power-down modes, in which power consumption is significantly reduced. Module standby mode
reduces power consumption by selectively halting on-chip module functions.
• Active mode
The CPU and all on-chip peripheral modules are operable on the system clock. The system
clock frequency can be selected from φosc, φosc/8, φosc/16, φosc/32, and φosc/64.
• Subactive mode
The CPU and all on-chip peripheral modules are operable on the subclock. The subclock
frequency can be selected from φw/2, φw/4, and φw/8.
• Sleep mode
The CPU halts. On-chip peripheral modules are operable on the system clock.
• Subsleep mode
The CPU halts. On-chip peripheral modules are operable on the subclock.
• Standby mode
The CPU and all on-chip peripheral modules halt. When the clock time-base function is
selected, timer A is operable.
• Module standby mode
Independent of the above modes, power consumption can be reduced by halting on-chip
peripheral modules that are not used in module units.
6.1 Register Descriptions
The registers related to power-down modes are listed below.
• System control register 1 (SYSCR1)
• System control register 2 (SYSCR2)
• Module standby control register 1 (MSTCR1)
LPW3003A_000020020200
Rev.5.00 Nov. 02, 2005 Page 75 of 418
REJ09B0028-0500