Laptop User Manual
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  Description  Initial Value 
Reserved [31:9]    
SDMMC Reset 
(SDreset) 
[8]  Reset whole sdmmc block. This bit is automatically cleared. 
0 = normal mode, 1 = SDMMC reset 
0 
Reserved [7:6]   0 
Clock Type 
(CTYP) 
[5]  Determines which clock type is used as SDCLK. 
0 = SD type, 1 = MMC type 
0 
Byte Order 
Type(ByteOrder) 
[4]  Determines byte order type when you read(write) data from(to) sd 
host FIFO with word boundary. 
0 = Type A, 1 = Type B 
0 
Receive SDIO 
Interrupt from card 
(RcvIOInt) 
[3]  Determines whether sd host receives SDIO Interrupt from the card 
or not(for SDIO). 
0 = ignore, 1 = receive SDIO Interrupt 
0 
Read Wait 
Enable(RWaitEn) 
[2]  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) 
0 
Reserved [1]    
Clock Out Enable 
(ENCLK) 
[0]  Determines whether SDCLK Out enable or not 
0 = disable(prescaler off), 1 = clock enable 
0 
* 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 
* Prescaler Value should be greater than zero. 










