Samsung S5PC100 User Manual page 978

S5PC100 USER'S MANUAL (REV1.0)
9.11 POWER CONTROL REGISTER
Power Control Register
• PWRCON0, R/W, Address = 0xED80_0029
• PWRCON1, R/W, Address = 0xED90_0029
• PWRCON2, R/W, Address = 0xEDA0_0029
This register contains the SD Command Argument.
PWRCON Bit
Reserved [7:4]
SELPWRLVL [3:1]
PWRON [0]
Reserved
SD Bus Voltage Select
If these bits are set, the Host Driver selects the voltage level for the SD
card. Before setting this register, the Host Driver checks the Voltage
Support bits in the Capabilities register. If an unsupported voltage is
selected, the Host System does not supply SD Bus voltage.
'111b' = 3.3V (Typ.)
'110b' = 3.0V (Typ.)
'101b' = 1.8V (Typ.)
'100b' − '000b' = Reserved
SD Bus Power
Before setting this bit, the SD Host Driver sets SD Bus Voltage Select.
If the Host Controller detects the No Card state, this bit is cleared.
If this bit is cleared, the Host Controller immediately stops driving CMD
and DAT[3:0] (tri-state) and drive SDCLK to low level.
'1' = Power on
'0' = Power off
Description
SD/MMC CONTROLLER
Reset Value
0
0
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