SH7751 Datasheet, PDF (343/1224 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

9. Power-Down Modes
9.2.4 Standby Control Register 2 (STBCR2)
Standby control register 2 (STBCR2) is an 8-bit readable/writable register that specifies the sleep
mode and deep sleep mode transition conditions. It is initialized to H'00 by a power-on reset via
the RESET pin or due to watchdog timer overflow.
Bit:
7
6
5
4
3
2
1
0
DSLP STHZ
—
—
—
— MSTP6 MSTP5
Initial value:
0
0
0
0
0
0
0
0
R/W: R/W
R/W
R
R
R
R
R/W
R/W
Bit 7—Deep Sleep (DSLP): Specifies a transition to deep sleep mode
Bit 7: DSLP
Description
0
Transition to sleep mode or standby mode on execution of SLEEP
instruction, according to setting of STBY bit in STBCR register (Initial value)
1
Transition to deep sleep mode on execution of SLEEP instruction*
Note: * When the STBY bit in the STBCR register is 0
Bit 6—STATUS Pin High-Impedance Control (STHZ): This bit selects whether the STATUS0
and 1 pins are set to high-impedance when in hardware standby mode.
Bit 6: STHZ
0
1
Description
Sets STATUS0, 1 pins to high-impedance when in hardware standby mode
(Initial value)
Drives STATUS0, 1 pins to LH when in hardware standby mode
Bits 5 to 2—Reserved: Only 0 should only be written to these bits; operation cannot be
guaranteed if 1 is written. These bits are always read as 0.
Bit 1—Module Stop 6 (MSTP6): Specifies that the clock supply to the store queue (SQ) in the
cache controller (CCN) is stopped. Setting the MSTP6 bit to 1 stops the clock supply to the SQ,
and the SQ functions are therefore unavailable. For details regarding the SH7751, see section 4.7,
Store Queues.
Bit 1: MSTP6
0
1
Description
SQ operating
Clock supply to SQ stopped
(Initial value)
Rev.4.00 Oct. 10, 2008 Page 245 of 1122
REJ09B0370-0400