User's Manual

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S3C2450X RISC MICROPROCESSOR SYSTEM CONTROLLER
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8.3 POWER MANAGEMENT REGISTERS (PWRMODE AND PWRCFG)
If you want to change the power management mode, you just write a bit(s) into PWRMODE register. Before
writing, you must configure condition to wake-up from the power down mode.
Register Address R/W Description Reset Value
PWRMODE 0x4C00_0040 R/W Power mode control register 0x0000_0000
PWRCFG 0x4C00_0060 R/W Power management configuration register 0x0000_0000
S3C2450 consists of three power-down modes, which are IDLE, (Deep)STOP, and SLEEP. The mode transition
from the NORMAL mode occurs when the appropriate value is written into PWRMODE & PWRCFG register. If
software tries to write illegal value, i.e., tries to set multiple power modes concurrently, then the write operation will
be ignored.
PWRMODE Bit Description Initial Value
RESERVED [31:17] RESERVED 0
STOP [16]
The system enters into STOP mode when this field is set to
‘1’.
0
SLEEP [15:0]
The system enters into SLEEP mode when this field is set to
‘0x2BED’. The bit pattern, ‘0x2BED’, represents “Go To BED”.
0
PWRCFG register controls the configuration of power mode transition.
PWRCFG Bit Description Initial Value
RESERVED [31:18] - 0x0000
STANDBYWFI_EN [17]
Enable entering of IDLE mode by STANDBYWFI.
0 = Disable, 1 = Enable
0
DEEP-STOP [16]
Enable the system enters DEEP-STOP mode.
If user set 16th register of PWRMODE reg. (ie. STOP) while
this bit is configured to ‘1’, the system enters DEEP-STOP
mode not STOP mode. To enter the DEEP-STOP mode
properly, this bit should be configured prior to setting STOP
mode bit.
0
SLEEP_CFG [15]
Enable wakeup source
0 = Wakeup sources are enabled depending on BATT_FLT in
sleep mode. If BATT_FLT pin is asserted logic ‘1’ system can
be exit from sleep mode by appropriate wakeup sources. If
not, system continuously remain it’s sleep state.
1 = Enable wakeup sources regardless of BATT_FLT in sleep
mode.
0
RESERVED [14:10] - 0x00
NFRESET_CFG [9]
Reset configuration when internal resets is generated
0 = Reset NAND flash controller.
1 = Do not reset NAND flash controller.
0