Samsung S3C6400X User Manual page 882

HSMMC CONTROLLER
SD BUS POWER CONTROL SEQUENCE
The sequence for controlling the SD Bus Power is described in Figure 27-6 and steps are described below:
(1) By reading the Capabilities register, get the support voltage of the Host Controller.
(2) Set SD Bus Voltage Select in the Power Control register with maximum voltage that the Host Controller
supports.
(3) Set SD Bus Power in the Power Control register to 1.
(4) Get the OCR value of all function internal of SD card.
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
27-6
Specifications and information herein are subject to change without notice.
(1)
Get the support voltage of the
Host Controller
(2)
Set SD Bus voltage select with
supported maximum voltage
(3)
Set SD Bus Power
(4)
Get OCR value of the SD Card
(5)
no change
SD Bus voltage
(6)
Clr SD Bus Power
(7)
Set SD Bus voltage select
(8)
Set SD Bus Power
Figure 27-6. SD Bus Power Control Sequence
S3C6400X RISC MICROPROCESSOR
START
changed ?
change
END