
MMC/SD/SDIO CONTROLLER
S3C2440A RISC MICROPROCESSOR
19-4
SDI SPECIAL REGISTERS
SDI Control Register (SDICON)
Register
Address
R/W
Description
Reset Value
SDICON
0x5A000000
R/W
SDI control register
0x0
SDICON
Bit
[31:9]
[8]
Description
–
Initial Value
Reserved
SDMMC Reset
(SDreset)
Reset whole sdmmc block. This bit is automatically cleared.
0 = Normal mode, 1 = SDMMC reset
0
Reserved
Clock Type (CTYP)
[7:6]
[5]
0
0
Determines which clock type is used as SDCLK.
0 = SD type, 1 = MMC type
Determines byte order type when you read(write) data from(to)
sd host FIFO with word boundary.
0 = Type A, 1 = Type B
Determines whether sd host receives SDIO Interrupt from the
card or not(for SDIO).
0 = Ignore, 1 = Receive SDIO Interrupt
Determines read wait request signal generate when sd host
waits the next block in multiple block read mode. This bit needs
to delay the next block to be transmitted from the card(for
SDIO).
0 = Disable(no generate), 1 = Read wait enable(use SDIO)
Byte Order
Type(ByteOrder)
[4]
0
Receive SDIO
Interrupt from card
(RcvIOInt)
[3]
0
Read Wait
Enable(RWaitEn)
[2]
0
Reserved
Clock Out Enable
(ENCLK)
[1]
[0]
Determines whether SDCLK Out enable or not
0 = Disable (prescaler off), 1 = Clock enable
0
NOTE:
Byte Order Type
Type A: (Access by Word) D[7:0]
→
D[15:8]
→
D[23:16]
→
D[31:24]
(Access by Halfword) D[7:0]
→
D[15:8]
Type B: (Access by Word) D[31:24]
→
D[23:16]
→
D[15:8]
→
D[7:0]
(Access by Halfword) D[15:8]
→
D[7:0]
SDI Baud Rate Prescaler Register (SDIPRE)
Register
Address
R/W
Description
Reset Value
SDIPRE
0x5A000004
R/W
SDI buad rate prescaler register
0x01
SDIPRE
Bit
Description
Initial Value
Prescaler Value
[7:0]
Determines SDI clock(SDCLK) rate as above equation.
Baud rate = PCLK / (Prescaler value + 1)
0x01
NOTE:
Prescaler Value should be greater than zero.