SDI Technologies SDIO Card User Manual

 

 

 

©Copyright 2000-2007 SD Card Association  

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The Card Information Structure provides more complete information about the card and the individual functions. 
The CIS is the common area to read information about all I/O functions that exist in a card. The design is based 
on the PC Card16 design standardized by PCMCIA. All cards that support I/O shall have a common CIS and a 
CIS for each function. The CIS is accessed by reads to a fixed area as shown in Table 6-5 This one area serves 
the card as a Common CIS and also as the storage area for each function. The common area and each function 
have a pointer to the start of its CIS within this memory space.  
 

0x0001000

- 0x017FFF 

Card Common Card Information Structure (CIS) area for card common and all functions 

0x018000-

0x01FFFF 

Reserved for Future Use 

 
The valid tuples (storage structures) from the PCMCIA specification and new tuples created for SDIO are 
defined in section 16.7. 
 

 
Multiple Function SDIO Cards shall have a separate set of Configuration registers for each function on the card. 
Multiple Function SDIO Cards shall use a combination of a CIS common to all functions on the card and a 
separate function-specific CIS specific to each function on the card. The common CIS describes features that 
are common to all functions on the card. Each function-specific CIS describes features specific to a particular 
function on the SDIO Card.  Functions are numbered sequentially beginning with 1. 
The CMD5 response indicates the total number of functions, which includes ‘dummy’ functions.  The host shall 
iterate through the CIS entries based on the CMD5 response. 
 
The ERROR status flag of an R5 response is type “E R X”, (see section 5.2.1) and can indicate an error in the 
previous command.  Since the host software needs a method to determine which function detected the error, a 
Multiple Function SDIO cards shall only return the R5 ERROR status flag in the subsequent command issued to 
the same function. 
 

 
The host sets the block size for a function’s multiple block transfers by writing to the 16-bit Function I/O Block 
Size register in the FBR (see Table 6-4).  The host shall not write this register using CMD53 with Block Mode set 
to 1.   If the card detects an invalid block size before executing CMD53 with Block Mode set to 1, it shall indicate 
an OUT_OF_RANGE error in the current response and shall not perform data transfer. This will also stop the 
interrupt period (see section 8.1.3)