SDI Technologies Computer Hardware SDIO Card User Guide

SD Specifications

Part E1

SDIO Simplified Specification

Version 2.00

February 8, 2007

Technical Committee

SD Card Association

SDIO Simplified Specification Version 2.00

Release of SD Simplified Specification

The following conditions apply to the release of the SD simplified specification ("Simplified Specification") by

the SD Card Association. The Simplified Specification is a subset of the complete SD Specification which is

owned by the SD Card Association.

Publisher:

SD Association

2400 Camino Ramon, Suite 375

San Ramon, CA 94583 USA

Telephone: +1 (925) 275-6615

Fax: +1 (925) 886-4870

E-mail: [email protected]

The SD Card Association

Notes:

This Simplified Specification is provided on a non-confidential basis subject to the disclaimers below. Any

implementation of the Simplified Specification may require a license from the SD Card Association or other

third parties.

Disclaimers:

The information contained in the Simplified Specification is presented only as a standard specification for SD

Cards and SD Host/Ancillary products and is provided "AS-IS" without any representations or warranties of

any kind. No responsibility is assumed by the SD Card Association for any damages, any infringements of

patents or other right of the SD Card Association or any third parties, which may result from its use. No

license is granted by implication, estoppel or otherwise under any patent or other rights of the SD Card

Association or any third party. Nothing herein shall be construed as an obligation by the SD Card

Association to disclose or distribute any technical information, know-how or other confidential information to

any third party.

SDIO Simplified Specification Version 2.00

Conventions Used in This Document

Naming Conventions

Some terms are capitalized to distinguish their definition from their common English meaning. Words not

capitalized have their common English meaning.

Numbers and Number Bases

Hexadecimal numbers are written with a lower case “h” suffix, e.g., FFFFh and 80h.

Binary numbers are written with a lower case “b” suffix (e.g., 10b).

Binary numbers larger than four digits are written with a space dividing each group of four digits, as in 1000 0101

0010b.

All other numbers are decimal.

Key Words

May:

Indicates flexibility of choice with no implied recommendation or requirement.

Shall:

Indicates a mandatory requirement. Designers shall implement such mandatory requirements to

ensure interchangeability and to claim conformance with the specification.

Should: Indicates a strong recommendation but not a mandatory requirement. Designers should give strong

consideration to such recommendations, but there is still a choice in implementation.

Application Notes

Some sections of this document provide guidance to the host implementers as follows:

Application Note:

This is an example of an application note.

iii

SDIO Simplified Specification Version 2.00

Table of Contents

1. General Description ................................................................................................................................. 1

1.1

1.2

1.3

SDIO Features .................................................................................................................................... 1

Primary Reference Document............................................................................................................. 1

Standard SDIO Functions.................................................................................................................... 1

2. SDIO Signaling Definition........................................................................................................................ 2

2.1

2.2

SDIO Card Types ................................................................................................................................ 2

SDIO Card modes............................................................................................................................... 2

2.2.1

2.2.2

2.2.3

SPI (Card mandatory support) ..................................................................................................... 2

1-bit SD Data Transfer Mode (Card Mandatory Support)............................................................. 2

4-bit SD Data Transfer Mode (Mandatory for High-Speed Cards, Optional for Low-Speed)......... 2

2.3

2.4

SDIO Host Modes ............................................................................................................................... 2

Signal Pins .......................................................................................................................................... 3

3. SDIO Card Initialization............................................................................................................................ 4

3.1

3.2

3.3

3.4

Differences in I/O card Initialization..................................................................................................... 4

The IO_SEND_OP_COND Command (CMD5)................................................................................. 10

The IO_SEND_OP_COND Response (R4)........................................................................................11

Special Initialization considerations for Combo Cards....................................................................... 12

3.4.1

3.4.2

3.4.3

3.4.4

3.4.5

Re-initialize both I/O and Memory.............................................................................................. 12

Using a Combo Card as SDIO only or SD Memory only after Combo Initialization.................... 12

Acceptable Commands after Initialization .................................................................................. 12

Recommendations for RCA after Reset..................................................................................... 12

Enabling CRC in SPI Combo Card............................................................................................. 14

4. Differences with SD Memory Specification.......................................................................................... 15

4.1

4.2

4.3

4.4

4.5

4.6

4.7

4.8

4.9

SDIO Command List ......................................................................................................................... 15

Unsupported SD Memory Commands............................................................................................... 15

Modified R6 Response...................................................................................................................... 16

Reset for SDIO.................................................................................................................................. 16

Bus Width.......................................................................................................................................... 16

Card Detect Resistor......................................................................................................................... 17

Timings.............................................................................................................................................. 17

Data Transfer Block Sizes................................................................................................................. 18

Data Transfer Abort ........................................................................................................................... 18

4.9.1

4.9.2

Read Abort................................................................................................................................. 18

Write Abort ................................................................................................................................. 18

4.10 Changes to SD Memory Fixed Registers .......................................................................................... 18

4.10.1 OCR Register............................................................................................................................. 19

4.10.2 CID Register............................................................................................................................... 19

4.10.3 CSD Register ............................................................................................................................. 19

4.10.4 RCA Register ............................................................................................................................. 19

4.10.5 DSR Register ............................................................................................................................. 19

4.10.6 SCR Register ............................................................................................................................. 19

4.10.7 SD Status................................................................................................................................... 19

4.10.8 Card Status Register.................................................................................................................. 19

5. New I/O Read/Write Commands............................................................................................................ 21

5.1

5.2

IO_RW_DIRECT Command (CMD52) .............................................................................................. 21

IO_RW_DIRECT Response (R5) ...................................................................................................... 22

5.2.1

5.2.2

5.3

5.3.1

CMD52 Response (SD modes).................................................................................................. 22

R5, IO_RW_DIRECT Response (SPI mode) ............................................................................. 23

IO_RW_EXTENDED Command (CMD53)........................................................................................ 24

CMD53 Data Transfer Format.................................................................................................... 25

SDIO Simplified Specification Version 2.00

5.3.2

Special Timing for CMD53 Multi-Block Read.............................................................................. 25

6. SDIO Card Internal Operation................................................................................................................ 26

6.1

6.2

6.3

6.4

6.5

6.6

6.7

6.8

6.9

Overview ........................................................................................................................................... 26

Register Access Time........................................................................................................................ 26

Interrupts........................................................................................................................................... 26

Suspend/Resume.............................................................................................................................. 27

Read Wait.......................................................................................................................................... 27

CMD52 During Data Transfer............................................................................................................ 27

SDIO Fixed Internal Map................................................................................................................... 27

Common I/O Area (CIA) .................................................................................................................... 28

Card Common Control Registers (CCCR)......................................................................................... 28

6.10 Function Basic Registers (FBR)........................................................................................................ 35

6.11 Card Information Structure (CIS)....................................................................................................... 37

6.12 Multiple Function SDIO Cards........................................................................................................... 37

6.13 Setting Block Size with CMD53......................................................................................................... 37

6.14 Bus State Diagram ............................................................................................................................ 38

7. Embedded I/O Code Storage Area (CSA) ............................................................................................. 39

7.1

7.2

CSA Access....................................................................................................................................... 39

CSA Data Format .............................................................................................................................. 39

8. SDIO Interrupts....................................................................................................................................... 40

8.1 Interrupt Timing ................................................................................................................................. 40

8.1.1

8.1.2

SPI and SD 1-bit Mode Interrupts .............................................................................................. 40

SD 4-bit Mode ............................................................................................................................ 40

Interrupt Period Definition .......................................................................................................... 40

Interrupt Period at the Data Block Gap in 4-bit SD Mode (Optional) .......................................... 40

Inhibited Interrupts (Removed Section)...................................................................................... 40

End of Interrupt Cycles............................................................................................................... 40

Terminated Data Transfer Interrupt Cycle .................................................................................. 41

Interrupt Clear Timing................................................................................................................. 41

8.1.3

8.1.4

8.1.5

8.1.6

8.1.7

8.1.8

9. SDIO Suspend/Resume Operation........................................................................................................ 42

10. SDIO Read Wait Operation..................................................................................................................... 43

11. Power Control......................................................................................................................................... 44

11.1 Power Control Overview.................................................................................................................... 44

11.2 Power Control support for SDIO Cards ............................................................................................. 44

11.2.1 Master Power Control ................................................................................................................ 44

11.2.2 Power Selection ......................................................................................................................... 45

11.2.3 High-Power Tuples..................................................................................................................... 45

11.3 Power Control Support for the SDIO Host......................................................................................... 45

11.3.1 Version 1.10 Host....................................................................................................................... 45

11.3.2 Power Control Operation............................................................................................................ 46

12. High-Speed Mode ................................................................................................................................... 47

12.1 SDIO High-Speed Mode.................................................................................................................... 47

12.2 Switching Bus Speed Mode in a Combo Card................................................................................... 47

13. SDIO Physical Properties ...................................................................................................................... 48

13.1 SDIO Form Factors ........................................................................................................................... 48

13.2 Full-Size SDIO .................................................................................................................................. 48

13.3 miniSDIO........................................................................................................................................... 48

14. SDIO Power............................................................................................................................................. 48

14.1 SDIO Card Initialization Voltages ...................................................................................................... 48

14.2 SDIO Power Consumption ................................................................................................................ 48

15. Inrush Current Limiting.......................................................................................................................... 50

16. CIS Formats ............................................................................................................................................ 51

16.1 CIS Reference Document ................................................................................................................. 51

SDIO Simplified Specification Version 2.00

16.2 Basic Tuple Format and Tuple Chain Structure................................................................................. 51

16.3 Byte Order Within Tuples .................................................................................................................. 51

16.4 Tuple Version .................................................................................................................................... 52

16.5 SDIO Card Metaformat...................................................................................................................... 52

16.6 CISTPL_MANFID: Manufacturer Identification String Tuple.............................................................. 53

16.7 SDIO Specific Extensions.................................................................................................................. 53

16.7.1 CISTPL_FUNCID: Function Identification Tuple......................................................................... 53

16.7.2 CISTPL_FUNCE: Function Extension Tuple.............................................................................. 54

16.7.3 CISTPL_FUNCE Tuple for Function 0 (common)....................................................................... 54

16.7.4 CISTPL_FUNCE Tuple for Function 1-7 .................................................................................... 55

16.7.5 CISTPL_SDIO_STD: Function is a Standard SDIO Function..................................................... 58

16.7.6 CISTPL_SDIO_EXT: Tuple Reserved for SDIO Cards............................................................... 58

Appendix A..................................................................................................................................................... 59

A.1 SD and SPI Command List.................................................................................................................... 59

Appendix B..................................................................................................................................................... 61

B.1 Normative References........................................................................................................................... 61

Appendix C..................................................................................................................................................... 62

C.1 Abbreviations and Terms................................................................................................................... 62

Appendix D..................................................................................................................................................... 64

SDIO Simplified Specification Version 2.00

Table of Tables

Table 3-1 OCR Values for CMD5..................................................................................................................... 10

Table 4-1 Unsupported SD Memory Commands ............................................................................................. 16

Table 4-2 R6 response to CMD3 ..................................................................................................................... 16

Table 4-3 SDIO R6 Status Bits......................................................................................................................... 16

Table 4-4 Combo Card 4-bit Control................................................................................................................ 17

Table 4-5 Card Detect Resistor States............................................................................................................. 17

Table 4-6 is blanked......................................................................................................................................... 17

Table 4-7 SDIO Status Register Structure ....................................................................................................... 20

Table 5-1 Flag data for IO_RW_DIRECT SD Response.................................................................................. 23

Table 5-2 IO_RW_ EXTENDED command Op Code Definition....................................................................... 24

Table 5-3 Byte Count Values ........................................................................................................................... 25

Table 6-1 Card Common Control Registers (CCCR) ....................................................................................... 29

Table 6-2 CCCR bit Definitions........................................................................................................................ 34

Table 6-3 Function Basic Information Registers (FBR).................................................................................... 35

Table 6-4 FBR bit and field definitions ............................................................................................................. 36

Table 6-5 Card Information Structure (CIS) and reserved area of CIA............................................................. 37

Table 11-1 Reference Tuples by Master Power Control and Power Select...................................................... 45

Table 16-1 Basic Tuple Format........................................................................................................................ 51

Table 16-2 Tuples Supported by SDIO Cards.................................................................................................. 52

Table 16-3 CISTPL_MANFID: Manufacturer Identification Tuple..................................................................... 53

Table 16-4 CISTPL_FUNCID Tuple................................................................................................................. 53

Table 16-5 CISTPL_FUNCE Tuple General Structure ..................................................................................... 54

Table 16-6 TPLFID_FUNCTION Tuple for Function 0 (common) .................................................................... 54

Table 16-7 TPLFID_FUNCTION Field Descriptions for Function 0 (common)................................................. 54

Table 16-8 TPLFID_FUNCTION Tuple for Function 1-7 .................................................................................. 55

Table 16-9 TPLFID_FUNCTION Field Descriptions for Functions 1-7............................................................. 57

Table 16-10 TPLFE_FUNCTION_INFO Definition........................................................................................... 57

Table 16-11 TPLFE_CSA_PROPERTY Definition ........................................................................................... 57

Table 16-12 CISTPL_SDIO_STD: Tuple Reserved for SDIO Cards................................................................ 58

Table 16-13 CISTPL_SDIO_EXT: Tuple Reserved for SDIO Cards................................................................. 58

Table A-14 SD Mode Command List................................................................................................................ 59

Table A-15 SPI Mode Command List............................................................................................................... 60

vii

SDIO Simplified Specification Version 2.00

Table of Figures

Figure 2-1 Signal connection to two 4-bit SDIO cards....................................................................................... 3

Figure 3-1 SDIO response to non-I/O aware initialization.................................................................................. 4

Figure 3-2 Card initialization flow in SD mode (SDIO aware host) .................................................................... 7

Figure 3-3 Card initialization flow in SPI mode (SDIO aware host).................................................................... 9

Figure 3-4 IO_SEND_OP_COND Command (CMD5)..................................................................................... 10

Figure 3-5 Response R4 in SD mode...............................................................................................................11

Figure 3-6 Response R4 in SPI mode..............................................................................................................11

Figure 3-7 Modified R1 Response....................................................................................................................11

Figure 3-8 Re-Initialization Flow for I/O Controller........................................................................................... 13

Figure 3-9 Re-Initialization Flow for Memory controller ................................................................................... 13

Figure 5-1 IO_RW_DIRECT Command........................................................................................................... 21

Figure 5-2 R5 IO_RW_DIRECT Response (SD modes).................................................................................. 22

Figure 5-3 IO_RW_DIRECT Response in SPI Mode....................................................................................... 23

Figure 5-4 IO_RW_EXTENDED Command..................................................................................................... 24

Figure 6-1 SDIO Internal Map.......................................................................................................................... 28

Figure 6-2 State Diagram for Bus State Machine............................................................................................. 38

viii

SDIO Simplified Specification Version 2.00

1. General Description

The SDIO (SD Input/Output) card is based on and compatible with the SD memory card. This compatibility

includes mechanical, electrical, power, signaling and software. The intent of the SDIO card is to provide

high-speed data I/O with low power consumption for mobile electronic devices. A primary goal is that an SDIO

card inserted into a non-SDIO aware host shall cause no physical damage or disruption of that host or it’s

software. In this case, the SDIO card should simply be ignored. Once inserted into an SDIO aware host, the

detection of the card proceeds via the normal means described in this specification with some extensions. In this

state, the SDIO card is idle and draws a small amount of power (15 mA averaged over 1 second). During the

normal initialization and interrogation of the card by the host, the card identifies itself as an SDIO card. The host

software then obtains the card information in a tuple (linked list) format and determines if that card’s I/O

function(s) are acceptable to activate. This decision is based on such parameters as power requirements or the

availability of appropriate software drivers. If the card is acceptable, it is allowed to power up fully and start the

I/O function(s) built into it.

1.1

SDIO Features

•

Targeted for portable and stationary applications

Minimal or no modification to SD Physical bus is required

Minimal change to memory driver software

Extended physical form factor available for specialized applications

Plug and play (PnP) support

Multi-function support including multiple I/O and combined I/O and memory

Up to 7 I/O functions plus one memory supported on one card.

Allows card to interrupt host

Operational Voltage range: 2.7-3.6V (Operational Voltage is used for Initialization)

Application Specifications for Standard SDIO Functions.

Multiple Form Factors:

•

Full-Size SDIO

miniSDIO

1.2

Primary Reference Document

This specification is based on and refers extensively to the SDA document:

SD Memory Card Specifications

Part 1 PHYSICAL LAYER SPECIFICATION Version 2.00 May 9, 2006

The reader is directed to this document for more information on the basic operation of SD cards. In addition,

other documents are referenced in this specification. A complete list can be found in appendix B.1.

This specification can apply to any released versions of Physical Layer Specification after Version 2.00.

1.3

Standard SDIO Functions

Associated with the base SDIO specification, there are several Application Specifications for Standard SDIO

Functions. These common functions such as cameras, Bluetooth cards and GPS receivers have a standard

interfaces are optional for any card vendor, but compliance with the standard allows the use of standard drivers

and applications which will increase the appeal of these cards to the consumer. Full information on these

standard interfaces can be found in the Application Specifications for Standard SDIO Functions maintained by

the SDA.

SDIO Simplified Specification Version 2.00

2. SDIO Signaling Definition

2.1

SDIO Card Types

This specification defines two types of SDIO cards. The Full-Speed card supports SPI, 1-bit SD and the 4-bit SD

transfer modes at the full clock range of 0-25MHz. The Full-Speed SDIO cards have a data transfer rate of over

100 Mb/second (10 MB/Sec). A second version of the SDIO card is the Low-Speed SDIO card. This card

requires only the SPI and 1-bit SD transfer modes. 4-bit support is optional. In addition, Low-Speed SDIO cards

shall support a full clock range of 0-400 KHz. The intended use of Low-Speed cards is to support low-speed I/O

capabilities with a minimum of hardware. The Low-Speed cards support such functions as modems, bar-code

scanners, GPS receivers etc. If a card is a ‘Combo card’ (memory plus SDIO) then Full-Speed and 4-bit

operation is mandatory for both the memory and SDIO portions of the card.

2.2

SDIO Card modes

There are 3 signaling modes defined for SD memory cards that also apply to SDIO Card:

2.2.1 SPI (Card mandatory support)

The SPI bus topology is defined in section 3.5.2 and the protocol is defined in sections 3.6.2 and 7 of the SD

Physical Specification Version 2.00. In this mode pin 8, which is undefined for memory, is used as the

interrupt pin. All other pins and signaling protocols are identical to the SD Physical Specification.

2.2.2

1-bit SD Data Transfer Mode (Card Mandatory Support)

This mode is identical to the 1 data bit (narrow) mode defined for SD Memory in section 3.6.1 of the SD

Physical Specification. In this mode, data is transferred on the DAT[0] pin only. In this mode pin 8, which is

undefined for memory, is used as the interrupt pin. All other pins and signaling protocols are identical to the

SD Memory specification.

2.2.3

4-bit SD Data Transfer Mode (Mandatory for High-Speed Cards, Optional for Low-Speed)

This mode is identical to the 4 data bit mode (wide) defined for SD Memory in section 3.6.1 of the SD

Physical Specification. In this mode, data is transferred on all 4 data pins (DAT[3:0]). In this mode the

interrupt pin is not available for exclusive use as it is utilized as a data transfer line. Thus, if the interrupt

function is required, a special timing is required to provide interrupts. See section 8.1.2 for details of this

operation. The 4-bit SD mode provides the highest data transfer possible, up to 100 Mb/sec.

2.3

SDIO Host Modes

If a SDIO aware host supports the SD transfer mode, it is recommended that both the 1-bit and 4-bit modes be

supported. While a SDIO host that supports only the 4-bit transfer mode is possible, its performance with a

Low-Speed SDIO card may be reduced. This is because the only means to transfer data to and from a

Low-Speed card would be the single byte per command transfer (using the IO_RW_DIRECT command

(CMD52) see 5.1).

SDIO Simplified Specification Version 2.00

2.4

Signal Pins

CLK

CMD

SD I/O Card

DAT[3:0]

SD Host

CLK

CMD

SD I/O Card

DAT[3:0]

Figure 2-1 Signal connection to two 4-bit SDIO cards

The rest of this chapter is not included in the Simplified Specification.

SDIO Simplified Specification Version 2.00

3. SDIO Card Initialization

3.1

Differences in I/O card Initialization

A requirement for the SDIO specification is that an SDIO card shall not cause non-I/O aware hosts to fail when

inserted. In order to prevent operation of I/O functions in non-I/O aware hosts, a change to the SD card

identification mode flowchart is needed. A new command (IO_SEND_OP_COND, CMD5) is added to replace

the ACMD41 for SDIO initialization by I/O aware hosts (see 3.2).

After reset or power-up, all I/O functions on the card are disabled and the I/O portion of the card shall not

execute any operation except CMD5 or CMD0 with CS=low. If there is SD memory installed on the card (also

called a combo card), that memory shall respond normally to all normal mandatory memory commands.

An I/O only card shall not respond to the ACMD41 and thus appear initially as an MMC card (See appendix B.1

for information on the MMC specification). The I/O only card shall also not respond to the CMD1 used to initialize

the MMC cards and appear as a non-responsive card. The host then gives up and disables this card. Thus, the

non-aware host receives no response from an I/O only card and force it to the inactive state. The operation of an

I/O card with a non-I/O aware host is shown in Figure 3-1 Note that the solid lines are the actual paths taken

while the dashed lines are not executed.

Reset

SPI

SPI Mode Idle

State

CMD0 + CS

asserted (0)

Idle State

Invalid

Cmd

CMD58

(optional)

Response

ACMD41

(arg = 00)

Busy

Response

CMD0

CMD1

CMD1 or

ACMD41

SDIO card is

Rejected

Invalid

Cmd

Busy

ACMD41

Response

Inactive State

arg = working

voltage

Response

Normal SPI

memory operation

Response

Normal SD

memory operation

SDIO card is

Rejected

Card is MMC

Figure 3-1 SDIO response to non-I/O aware initialization

SDIO Simplified Specification Version 2.00

An SDIO aware host sends CMD5 prior to the CMD55/ACMD41 pair, and thus would receive a valid OCR in the

R4 response to CMD5 and continue to initialize the card. Figure 3-2 shows the operation of an SDIO aware host

operating in the SD modes and Figure 3-3 shows the same operation for a host that operates in the SPI mode.

If the I/O portion of a card has received no CMD5, the I/O section remains inactive and shall not respond to any

command except CMD5. A combo card stays in the memory-only mode. If no memory is installed on the card

(i.e. an I/O only card in a non-SDIO aware host) the card would not respond to any memory command. This

satisfies the condition where a user uses some I/O function on the card such as Ethernet to load a music file to

the memory function of that card. The card is then removed and inserted into a non-SDIO aware host. That host

would not enable the I/O function (no CMD5) so would appear to the player as a memory-only card. If the host

were I/O aware, it would send the CMD5 to the card and the card would respond with R4. The host reads that R4

value and knows the number of available I/O functions and about the existence of any SD memory.

After the host has initialized the I/O portion of the card, it then reads the Common Information Area (CIA) of the

card (see 6.8). This is done by issuing a read command, starting with the byte at address 0x00, of I/O function 0.

The CIA contains the Card Common Control Registers (CCCR) and the Function Basic Registers (FBR). Also

included in the CIA are pointers to the card’s common Card Information Structure (CIS) and each individual

function’s CIS. The CIS structure is defined in section 16. The CIS includes information on power, function,

manufacturer and other things the host needs to determine if the I/O function(s) is appropriate to power-up. If the

host determines that the card should be activated, a register in the CCCR area enables the card and each

individual function. At this time, all functions of the I/O card are fully available. In addition, the host can control

the power consumption and enable/disable interrupts on a function-by-function basis. This access to I/O does

not interfere with memory access to the card if present.

Combo Cards can accept CMD15 with RCA=0000, as described in, but there is an exception for SD memory

only cards. Memory only cards require a non-zero RCA before the host may issue CMD15. Thus, CMD15 shall

be issued after CMD3 in the Standby state. In the case of ACMD41, it shall accept RCA=0x0000.

As shown in Figure 3-2 and Figure 3-3, an SDIO aware host shall send CMD5 arg=0 as part of the initialization

sequence after either Power On or a CMD 52 with write to I/O Reset. Sending CMD5 arg=0 that has not been

preceded by one of these two reset conditions shall not result in either the host or card entering the initialization

sequence.

SDIO Simplified Specification Version 2.00

Re-init Memory

MEM=0

Power On

Re-init IO

IO=0

IO=0, MEM=0

CMD52 IO Reset

CMD0 Pin1=High

CMD8

CMD8 is required to support

High Capacity Memory.

Error Response

No Response

F8=0

Check Response

Good Response

F8=1

Unusable card

Skip IO Initialize or IO=1

Test IO Flag

Execute IO Initialize & IO=0

Get IO OCR

CMD5 Arg=0

No Response

NF=0 or OCR invalid

Check Response

NF>0 & OCR valid

Set New Voltage (if needed)

CMD5 Arg=WV

IORDY=0

No Response

1sec Timeout

Check Response

IORDY=1

IO Initialized

IO=1

Unusable card

(Inactive State)

MP=0

Test MP Flag

MP=1

SDIO Simplified Specification Version 2.00

Skip memory initialize or MEM=1

Test MEM Flag

Execute memory initialize & MEM=0

Get memory OCR

OCR invalid

ACMD41 Arg=0

No Response

Check Response

OCR valid

Set New Voltage (if needed)

High Capacity Support Host: HCS=1

ACMD41 Arg=HCS, WV

MRDY=0

No Response

1sec Timeout

Check Response

MRDY=1

Memory Initialized

If F8=1, CCS is valid

MEM=1

Unusable card

(Inactive State)

CMD2

IO=1

Test IO Flag

IO=0

CMD3

CMD15 RCA=0

Test Flags

IO=0, MEM=1

IO=1, MEM=0

IO=1,

MEM=1

IO Only

Card

Not SD

Card

Test CCS

Unusable card

(Inactive State)

CCS=0

CCS=1

CCS=0

CCS=1

Standard

Capacity

Memory

High

Standard

Capacity

Combo

Card

High

Capacity

Combo

Card

Capacity

Memory

Only Card

Variables

NF:

MP:

Number of I/O Functions (CMD5 Response)

Memory Present Flag (CMD5 Response)

CCS:

Flags

IO:

MEM:

F8:

Card Capacity Status (ACMD41 Response)

IORDY: I/O Power-up Status (C bit in the CMD5 response)

MRDY:

HCS:

I/O Functions Initialized Flag

Memory Initialized Flag

CMD8 Flag

Memory Power-up Status (OCR Bit31)

Host Capacity Support (ACMD41 Argument)

Figure 3-2 Card initialization flow in SD mode (SDIO aware host)

SDIO Simplified Specification Version 2.00

Re-init Memory

MEM=0

Power On

Re-init IO

IO=0

IO=0, MEM=0

CMD0 CS=Low

CMD8

CMD52 IO Reset

CMD8 is required to support

High Capacity Memory.

Error Response

Illegal Command

F8=0

Check Response

Good Response

F8=1

Unusable card

Skip IO Initialize or IO=1

Test IO Flag

Execute IO Initialize & IO=0

Get IO OCR

CMD5 Arg=0

Illegal Command

NF=0 or OCR invalid

Check Response

NF>0 & OCR valid

Set New Voltage (if needed)

CMD5 Arg=WV

IORDY=0

1sec Timeout

Check Response

IORDY=1

IO Initialized

IO=1

MP=0

Test MP

MP=1

SDIO Simplified Specification Version 2.00

Skip memory initialize or MEM=1

Test MEM Flag

Execute memory initialize & MEM=0

Get memory OCR

CMD58

Illegal Command

OCR invalid

Check Response

OCR valid

Set New Voltage (if needed)

High Capacity Support Host: HCS=1

ACMD41 Arg=HCS, WV

IDLE=1

1sec Timeout

Check Response

IDLE=0

Memory Initialized

MEM=1

If F8=1, CMD58 is required

to get CCS. If F8=0, CSS=0.

Illegal Command

CMD58

IO=0, MEM=0

IO=1, MEM=1

Test Flags

IO=1,

IO=0, MEM=1

MEM=0

IO Only

Card

Test CCS

Not SD

Card

Unusable card

CCS=0

CCS=1

CCS=0

CCS=1

Standard

Capacity

Memory

High

Standard

Capacity

Combo

Card

High

Capacity

Combo

Card

Capacity

Memory

Only Card

Variables

NF:

MP:

Number of I/O Functions (CMD5 Response)

Memory Present Flag (CMD5 Response)

CCS:

Flags

IO:

MEM:

F8:

Card Capacity Status (ACMD41 Response)

IORDY: I/O Power-up Status (C bit in the CMD5 response)

MRDY:

HCS:

I/O Functions Initialized Flag

Memory Initialized Flag

CMD8 Flag

Memory Power-up Status (OCR Bit31)

Host Capacity Support (ACMD41 Argument)

Figure 3-3 Card initialization flow in SPI mode (SDIO aware host)

SDIO Simplified Specification Version 2.00

3.2

The IO_SEND_OP_COND Command (CMD5)

Figure 3-4 shows the format of the IO_SEND_OP_COND command (CMD5). The function of CMD5 for SDIO

cards is similar to the operation of ACMD41 for SD memory cards. It is used to inquire about the voltage range

needed by the I/O card. The normal response to CMD5 is R4 in either SD or SPI format. The R4 response in SD

mode is shown in Figure 3-5 and the SPI version is shown in Figure 3-6.

S D Command Index

000101b

Stuff

Bits

I/O OCR

CRC7

1 1

Figure 3-4 IO_SEND_OP_COND Command (CMD5)

The IO_SEND_OP_COND Command contains the following fields:

S(tart bit):

Start bit. Always 0

D(irection):

Command Index:

Stuff Bits:

Direction. Always1 indicates transfer from host to card.

Identifies the CMD5 command with a value of 000101b

Not used, shall be set to 0.

I/O OCR:

Operation Conditions Register. The supported minimum and maximum values

for VDD. The layout of the OCR is shown in Table 3-1. See section 4.10.1 for

additional information.

7 bits of CRC data

End bit, always 1

CRC7:

E(nd bit):

I/O OCR bit

position

VDD Voltage Window

(in Volts)

Reserved

2.0-2.1

0-3

2.1-2.2

2.2-2.3

2.3-2.4

2.4-2.5

2.5-2.6

2.6-2.7

2.7-2.8

2.8-2.9

2.9-3.0

3.0-3.1

3.1-3.2

3.2-3.3

3.3-3.4

3.4-3.5

3.5-3.6

Table 3-1 OCR Values for CMD5

The SDIO Version 2.00 cards shall support the operational voltage range 2.7-3.6V and are not necessary to

support the voltage range 2.0-2.7V for basic communication. The hosts, which support SDIO Version 2.00, shall

not use voltage range 2.0-2.7V for basic communication.

SDIO Simplified Specification Version 2.00

3.3

The IO_SEND_OP_COND Response (R4)

An SDIO card receiving CMD5 shall respond with a SDIO unique response, R4. The format of R4 for both the

SD and SPI modes is:

S D Reserved

Number

of I/O

functions

Memory

Present

Stuff

Bits

I/O OCR

Reserved

1 1

Figure 3-5 Response R4 in SD mode

Modified

Number

of I/O

functions

Memory Stuff Bits

Present

I/O OCR

Figure 3-6 Response R4 in SPI mode

The Response, R4 contains the following data:

S(tart bit):

D(irection):

Reserved:

Start bit. Always 0

Direction. Always 0. Indicates transfer from card to host.

Bits reserved for future use. These bits shall be set to 1.

Set to 1 if Card is ready to operate after initialization

I/O OCR:

Operation Conditions Register. The supported minimum and maximum values

for VDD. The layout of the OCR is shown in Table 3-1. See section 4.10.1 for

additional information.

Memory Present:

Set to 1 if the card also contains SD memory. Set to 0 if the card is I/O only.

Number of I/O Functions: Indicates the total number of I/O functions supported by this card. The range is 0-7.

Note that the common area present on all I/O cards at Function 0 is not included in

this count. The I/O functions shall be implemented sequentially beginning at

function 1.

Modified R1:

The SPI R1 response byte as described in the SD Physical Specification modified

for I/O as follows:

1 = in idle state

RFU (always 0)

1 = illegal command

1 = COM CRC error

1 = Function number error

RFU (always 0)

1 = parameter error

Start Bit (always 0)

Figure 3-7 Modified R1 Response

Not used, shall be set to 0.

Stuff Bits:

SDIO Simplified Specification Version 2.00

Once an SDIO card has received a CMD5, the I/O portion of that card is enabled to respond normally to all

further commands. This I/O enable of the functions within the I/O card shall remain set until a reset, power cycle

or CMD52 with write to I/O reset is received by the card. Note that a SD memory only card may respond to a

CMD5. The proper response for a memory only card would be Memory Present = 1 and Number of I/O

Functions = 0. A memory only card built to SD Memory Card specification version 1.01 would detect the CMD5

as an illegal command and not respond. Note that unlike the similar memory command ACMD41, The SPI

response to CMD5 does contain the OCR value from the card.

The I/O aware host sends CMD5. If the card responds with response R4 within the timeout value of Ncr as

defined in the SD Physical Specification, the host determines the card’s configuration based on the data

contained within the R4.

3.4

Special Initialization considerations for Combo Cards

The host must be aware of some special situations when initializing a Combo card (SDIO plus SD Memory on

the same card). This is caused because an implementation of the Combo card could actually use 2 separate

controllers (Memory and I/O) in the same package and sharing the same bus lines. It important for the host to

both detect and properly configure both parts (controllers) of a Combo card in order to prevent conflicts between

the SDIO and the SD memory controller. These concerns are caused due to the different response to a reset

(hard or soft) by the two controllers. Another concern is the value of the RCA (Relative Card Address) that exists

within the Memory controller.

Note that this consideration is for the SD 1-bit and SD 4-bit modes only. In The SPI mode, card select/de-select

is accomplished using the hardware CS line rather than the RCA.

3.4.1

Re-initialize both I/O and Memory

When the host re-initializes both I/O and Memory controllers, it is strongly recommended that the host either

execute a power reset (power off then on) or issues a reset commands to both controllers prior to any other

operation. If the host chooses to use the reset commands, it shall issue CMD52 (I/O Reset) first, because it

cannot issue CMD52 after CMD0 (see 4.4). After the reset, the host shall re-initialize both the I/O and Memory

controller as defined in Figure 3-2.

3.4.2

Using a Combo Card as SDIO only or SD Memory only after Combo Initialization

If a host intends to use only the SDIO or the Memory portion of a Combo Card, it is strongly recommended that

the host power reset (power off then on) or issues reset commands to both controllers prior to any other

operation. If the host chooses to use the reset commands, it shall issue CMD52 (I/O Reset) first, because it

cannot issue CMD52 after CMD0 (see 4.4). After the resets, the host re-initializes either the I/O and Memory

controller as defined in Figure 3-2.

3.4.3

Acceptable Commands after Initialization

When the host re-initializes a Combo card, the acceptable commands that the host can issue are restricted until

the I/O controller is placed into the command state and memory controller enters the transfer state. The kinds of

prohibited commands are identified in the next section. Combo cards may not work correctly when the host

issues these prohibited commands. The proper command sequence for the I/O controller and the memory

controller are shown below. Note that CMD15 (GO_INACTIVE_STATE) can be sent at any time after

initialization in order to send any addressed memory controller to the inactive state.

3.4.4

Recommendations for RCA after Reset

Important Note: The RCA specification was not fully defined in SDIO Specification Ver1.0. There are two types

of card (SDIO or Combo) with different responses to CMD0 or SDIO reset. The possible responses are:

SDIO Simplified Specification Version 2.00

The card clears RCA to 0x0000

The card keeps current RCA value

Card RCA Select/Deselect

Mem State I/O State

Command Sequence

Combo Init

(After CMD7 with the correct RCA)

Select

xxxx Sel Desel

xxxx

Deselect

tran

cmd

RCA1

cmd

idle

Issue CMD52 (Reset I/O)

RCA1

Re-initialize I/O (CMD5)

Issue CMD3

idle

xxxx

idle stby

stby cmd

tran

RCA2

Deselect

Issue CMD7 with the correct RCA

(and Data Transfer)

RCA2

Desel Sel

Figure 3-8 Re-Initialization Flow for I/O Controller

Figure 3-8 shows the re-initialization flow for the I/O controller of a Combo card. The flow of commands on the

left side is matched with the RCA and controller states on the right side. The RCA value of xxxx denotes an RCA

value of either 0x0000 or the prior RCA value. For new controller designs, a reset RCA value of 0x0000 is

recommended. The host shall not issue any commands to the Combo Card except for CMD0, CMD5, CMD3 or

CMD7 until the I/O controller has transitioned to the cmd state.

Card RCA Select/Deselect

Mem State I/O State

Command Sequence

Combo Init

(After CMD7 with the correct RCA)

RCA1

Select

Sel Desel

Deselect

tran

cmd

xxxxh

Issue CMD0 (Reset Memory)

Re-initialize Memory (ACMD41)

Issue CMD2

tran

idle

RCA1

xxxxh

idle ready

ready ident

ident stby

stby tran

Deselect

xxxxh

Issue CMD3)

Deselect

RCA2

Issue CMD7 with the correct RCA

(and Data Transfer)

RCA2

Desel Sel

Figure 3-9 Re-Initialization Flow for Memory controller

SDIO Simplified Specification Version 2.00

Figure 3-9 shows the equivalent command flow to re-initialize the memory controller of a Combo card. The RCA

value of xxxxh denotes an RCA value of either 0x0000 or the prior RCA value. For new controller designs, a

reset value of 0x0000 is recommended. The important fact for the host designer to note is that the host shall not

issue any commands except for CMD0, ACMD41 (with RCA=0x0000), CMD2, CMD3 or CMD7 to the Combo

Card until the memory controller has transitioned to the tran state.

3.4.5

Enabling CRC in SPI Combo Card

When receiving CMD59, Combo cards shall synchronize CRC enable in both SDIO and memory portions of the

card. If a host enables CRC using CMD59 and subsequently re-initializes either the I/O or memory controller,

the CRC for that controller will be off by default and the host shall issue a CMD59 to re-enable CRC. When

CMD59 is received, Combo Cards return the R1 response token while SDIO only cards return the modified R1

response token.

SDIO Simplified Specification Version 2.00

4. Differences with SD Memory Specification

4.1

SDIO Command List

Table A-14 shows the list of commands accepted by SD memory and SDIO cards when using the SD bus

interface. Table A-15 shows the list of commands accepted by SD memory and SDIO cards when using the SPI

bus interface.

4.2

Unsupported SD Memory Commands

Several commands required for SD Memory cards are not supported by either SDIO-only cards or the I/O

portion of Combo cards. Some of these commands have no use in SDIO cards such as Erase commands and

thus are not supported in SDIO. In addition, there are several commands for SD memory cards that have

different commands when used with the SDIO section of a card. Table 4-1 lists these SD Memory commands

and the equivalent SDIO commands. For a complete list of supported and unsupported commands, see Table

A-14 and Table A-15.

SD Memory

Command

CMD0

SDIO

Command

Comment

CMD52 (write to The reset command (CMD0) is only used for memory or the

I/O reset in

CCCR)

memory portion of Combo cards. In order to reset an I/O only

card or the I/O portion of a combo card, use CMD52 to write a

1 to the RES bit in the CCCR (bit 3 of register 6). Note that in

the SD mode, CMD0 is only used to indicate entry into SPI

mode and shall be supported. An I/O only card or the I/O

portion of a combo card is not reset with CMD0

CMD12

CMD16

CMD52 (write to In order to abort the block transfer of data, SD memory use

I/O abort)

CMD12. In order to abort an I/O transaction, use CMD52 to

write to the abort register in the CCCR (bits 2:0 of register 6)

See 4.8 for details.

CMD52 (write to CMD16 sets the block length for SD memory. In order to set

I/O Block

Length)

NONE

the block length for each I/O function, use CMD52 to write the

block length in the FBR

CMD2

CMD4

CMD9

CMD10

CMD13

The CID register does not exist in an SDIO only card

The DSR register does not exist in an SDIO only card

The CSD register does not exist in an SDIO only card

The CID register does not exist in an SDIO only card

An SDIO only card or the I/O portion of a combo card does not

support the same SEND_STATUS (CMD13) protocol the SD

memory uses. See 4.10.8.

ACMD6

CMD52 (write to SET_BUS_WIDTH is handled by a write to the CCCR. See

Bus_Width [1:0] 4.4 for details.

in CCCR)

ACMD13

ACMD41

NONE

CMD5

The SD Status register does not exist in an SDIO only card

SDIO cards and hosts use the IO_SEND_OP_COND

Command (CMD5). See 3.2

ACMD42

CMD52

In the SD mode, the pull-up resistor on DAT[3] is controlled by

writing to the CD Disable bit in the CCCR. For Combo Cards,

this resistor is enabled unless both the memory and the I/O

control registers are set to disable the resistor. For details, see

section 4.6

ACMD51

CMD17,

NONE

CMD53

The SCR register does not exist in an SDIO only card

I/O block operations use CMD53, rather than memory block

SDIO Simplified Specification Version 2.00

SD Memory

Command

CMD18,

SDIO

Command

Comment

read/write commands.

CMD24,

CMD25

Table 4-1 Unsupported SD Memory Commands

4.3

Modified R6 Response

The normal response to CMD3 by a memory card is R6 as shown in Table 4-2. The card status bits (23-8) are

changed when CMD3 is sent to an I/O only card. In this case, the 16 bits of response shall be the SDIO-only

values shown in Table 4-3

Bit position

Width (bits)

Value

‘0’

[45:40]

[39:8] Argument field

[7:1]

‘1’

end

bit

Description Start Direction Command New published RCA

[15:0] Card status

(see Table 4-3)

CRC7

bit

index

[31:16] of the card

(‘000011’)

Table 4-2 R6 response to CMD3

Bits

Identifier

Type

Value

Description

Clear

Condition

COM_CRC_ERROR

ILLEGAL_COMMAND

ERROR

E R

’0’= no error

’1’= error

’0’= no error

’1’= error

The CRC check of the previous

command failed

Command not legal for the card

state

A general or an unknown error

occurred during the operation

E R X ’0’= no error

’1’= error

12: 0

Undefined. Should read as 0 for SDIO only cards. Host should ignore these bits.

Note: Please refer to sections 7.3.4 of the SD Physical Specification for explanation of the entries in the Type

and Clear Condition columns.

Table 4-3 SDIO R6 Status Bits

4.4

Reset for SDIO

In order to reset all functions within an SDIO card or the SDIO portion of a combo card, a method different than

that used for SD memory is defined. The reset command (CMD0) is only used for memory or the memory

portion of Combo cards. In order to reset an I/O only card or the I/O portion of a combo card, use CMD52 to write

a 1 to the RES bit in the CCCR (bit 3 of register 6). Note that in the SD mode, CMD0 is only used to indicate

entry into SPI mode and shall be supported. An I/O only card or the I/O portion of a combo card is not reset by

CMD0.

4.5

Bus Width

For a SD memory card, the bus width for SD mode is set using ACMD6. The SDIO card uses a write to the

CCCR using CMD52 to select bus width. In the case of a combo card, both selection methods exist. In this case,

the host shall set the bus width in both locations by issuing both the ACMD6 and the CCCR write using CMD52

with the same width before starting any data transfers. For details on changing the bus for an SDIO card, see

Table 6-2. . For a Combo Card, changing bus width is handled as shown in Table 4-4.

SDIO Simplified Specification Version 2.00

I/O

Initialized

Memory

Not

Control Method

CCCR

Initialized

Not

Initialized

ACMD6

Initialized

Initialized Initialized CCCR & ACMD6

Table 4-4 Combo Card 4-bit Control

As shown in Table 4-4, if only the I/O function of a combo card is active, only writing to the CCCR is required

change the bus width mode. If only memory is active then ACMD6 is all that is needed to change bus widths. If

both I/O and Memory are active then both CCCR and ACMD6 are needed to change the bus width. In the

combo card, both the memory and I/O controllers shall be set to the same bus width

Note that Low-Speed SDIO cards support 4-bit transfer as an option. When communicating with a Low-Speed

SDIO card, the host shall first determine if the card supports 4-bit transfer prior to attempting to select that mode.

If a Combo card supports the lock/unlock operation, it cannot change bus width of a locked card and returns an

illegal command error to a bus width switch command. The host needs to unlock the card by CMD42 before

changing bus width. This also implies that the host should not change bus width during initialization before

managing a locked card.

4.6

Card Detect Resistor

SD memory and I/O cards use a pull-up resistor on DAT[3] to detect card insertion. The procedure to

enable/disable this resistor is different between SD memory and SDIO. SD memory uses ACMD42 to control

this resistor while SDIO uses writes to the CCCR using CMD52. In the case of a combo card, both control

locations exist and shall be managed by the host. For a combo card, the resistor is enabled only when both the

memory and the I/O control registers have the resistor enabled. That is, after a power on, the host shall disable

the resistor using ACMD42 to the memory controller or a CCCR write to the SDIO controller since the resistor

enable is a logical AND of the two enables. Table 4-5 shows the effect of each resistor enable on the card’s

resistor. After power-up, both locations default to resistor enabled. Note that after an I/O reset, the I/O resistor

enable is not changed. Note that the SDIO Specification Version 1.00 required that both the SDIO and Memory

resistor be disabled in order for the resistor to actually be disabled (logical OR of the 2 enables). Combo cards

built to that specification require the host to disable both enables. It is recommended the host disable both

enables of any combo card to avoid problems with the difference between 1.0 and current specification based

cards.

I/O Resistor

Enabled

Disabled

Memory Resistor

Enabled

Card Resistor

Resistor Connected

Resistor Disconnected

Disabled

Enabled

Disabled

Table 4-5 Card Detect Resistor States

4.7

Timings

This section is not included in the Simplified Specification.

Table 4-6 is blanked

SDIO Simplified Specification Version 2.00

4.8

Data Transfer Block Sizes

SDIO cards may transfer data in either a multi-byte (1 to 512 bytes) or an optional block format, while the SD

memory cards are fixed in the block transfer mode. The SD Physical Specification limits the block size for data

transfer to powers of 2 (i.e. 512, 1024, 2048) unless using partial read and write. The SDIO Specification allows

any block size from 1 byte to 2048 bytes in order to accommodate the various natural block sizes for I/O

functions. Note that an SDIO card function may define a maximum block size or byte count in the CIS that is

smaller than the maximum values described above.

4.9

Data Transfer Abort

A host communicating with a SD memory card uses CMD12 to abort the transfer of read or write data to/from the

card. For an SDIO card, CMD12 abort is replaced by a write to the ASx bits in the CCCR. Normally, the abort is

used to stop an infinite block transfer (block count=0). If an exact number of blocks are to be transferred, it is

recommended that the host issue a block command with the correct block count, rather than using an infinite

count and aborting the data at the correct time.

4.9.1

Read Abort

The host may issue an I/O abort by writing to the CCCR at any time during I/O extended read operation. The

data transmission stops 2 clocks cycles after the end bit of the I/O abort command, even If the card has already

begun transferring an unwanted data block while the host is issuing the abort.

The rest of this section is not included in the Simplified Specification.

4.9.2

Write Abort

The host may issue an I/O abort by writing to the CCCR at any time between data blocks during I/O extended

write operation. In this case, the final block transfer (including the CRC response from the card) shall have been

completed. This requires that the end bit of the I/O abort command should appear a maximum of two clocks

before the end bit of the CRC response to the last data block. Note that the I/O abort command may be sent any

time after the CRC response to the last data block. The host shall not abort in the middle of a write block. After

the I/O abort is sent to the card, the card signals ‘Busy’ (by pulling DAT[0] line to ‘0’) until it has finished

processing the last transferred data block. During that Busy period, the host may release the bus by writing to

the CCCR BR bit. There exist some special cases when the abort is issued near the end of the CRC response to

a write multiple command.

The rest of this section is not included in the Simplified Specification.

4.10 Changes to SD Memory Fixed Registers

The SD Physical Specification Version 1.01 defines 7 fixed card registers. They are:

1. OCR Register (32 bits)

2. CID Register (128 bits)

3. CSD Register (128 bits)

4. RCA Register (16 bits)

5. DSR Register (16 bits, optional)

6. SCR Register (64 bits)

7. SD_CARD_STATUS (512 bits)

In addition, within an SD memory card there is a status register whose value is returned to the host in the form of

several responses (i.e. the R1b response). An SDIO only card eliminates some registers and changes some of

the bits in the remaining registers. The description of these register changes follows:

SDIO Simplified Specification Version 2.00

4.10.1 OCR Register

All SD cards (memory, I/O and combo) shall have at least one OCR register. If the card is a combo card, it may

have two OCR’s (one for memory and one for I/O). The memory portion of a combo card has an OCR accessed

using ACMD41 and CMD58. The I/O portion of a card has an OCR with the same structure that is accessed via

CMD5. If there are multiple OCR’s the voltage range may not be identical. Some I/O functions may have a wider

VDD range than that reflected in the I/O OCR register. The I/O OCR shall be the logical AND of the voltage

ranges(s) of all I/O functions. Note that the I/O OCR format is different from the memory version in that it is only

24 bits long. For details, see Table 3-1. The per-function voltage for each I/O function can be read in the CIS for

the card.

4.10.2 CID Register

There shall be a maximum of one CID register per SD card. If the card contains both memory and I/O, the CID

portion of the card. If the card is I/O only, the CID register and the associated access command (CMD10) are

not supported. If the host attempts to access this register in an I/O only card, a card in SPI mode shall respond

with an "Invalid Command" error response and a card in SD mode shall not respond.

4.10.3 CSD Register

There shall be a maximum of one CSD register per SD card. If the card contains both memory and I/O, the CSD

portion of the card. If the card is I/O only, the CSD register and the associated access command (CMD9) are not

supported. If the host attempts to access this register in an I/O only card, a card in SPI mode shall respond with

an "Invalid Command" error response and a card in SD mode shall not respond.

4.10.4 RCA Register

There shall only be one RCA register per SD card. The RCA value shall apply to the card as a whole. All

functions and any memory share the same card address.

4.10.5 DSR Register

SDIO only cards do not support the DSR register. In the case of combo cards, support is optional as defined in

the SD Physical Specification.

4.10.6 SCR Register

There shall be a maximum of one SCR register per SD card. If the card contains both memory and I/O, the SCR

portion of the card. If the card is I/O only, the SCR register and the associated access command (ACMD51) are

not supported. If the host attempts to access this register in an I/O only card, a card in SPI mode shall respond

with an "Invalid Command" error response and a card in SD mode shall not respond.

4.10.7 SD Status

There shall be a maximum of one SD Status register per SD card. If the card contains both memory and I/O, the

SD Status register information is unchanged from the SD 1.01 version and reflects the information from the

memory portion of the card. If the card is I/O only, the SD Status register and the associated access command

(ACMD13) are not supported. If the host attempts to access this register in an I/O only card, a card in SPI mode

shall respond with an "Invalid Command" error response and a card in SD mode shall not respond.

4.10.8 Card Status Register

The structure of the SDIO status register is shown in Table 4-7. For SDIO specific operations in the SD mode

that return the card status register contents (i.e. the response to CMD7), some bits are not applicable to I/O

operations and shall be returned as 0. These unused bits are identified as type N/A. For combo cards, the

values returned shall reflect the memory status. The CURRENT_STATE bits (12:9) shall reflect the memory

Controller State. For an I/O only card, the unused bits are 0 and the Current_State bits (12:9) shall be 0xF (15) to

SDIO Simplified Specification Version 2.00

identify it as an I/O only response.

I/O specific status is reported by I/O response and Memory specific status is reported by Memory response

except for the following case: In the SD bus mode, the card shall not respond to an Illegal Command or a

command with a CRC error. The indication of those two error cases shall be given by the card in the following

command’s response. This is true for an I/O only card as well as for combo cards, even in cases where the

erroneous command and the command that follows are not targeting the same card module (Memory or I/O).

Clear

Bit

Identifier

OUT_OF_RANGE

Type

E R

Value

’0’= no error

’1’= error

Description

Condition

The command’s argument was out

of the allowed range for this card.

Not used with SDIO operation

The CRC check of the previous

command failed. (Note 1)

ADDRESS_ERROR

BLOCK_LEN_ERROR

ERASE_SEQ_ERROR

ERASE_PARAM

N/A

E R

WP_VIOLATION

CARD_IS_LOCKED

LOCK_UNLOCK_FAILED

COM_CRC_ERROR

’0’= no error

’1’= error

ILLEGAL_COMMAND

E R

’0’= no error

’1’= error

Previous command not legal for the

card state. (Note 2)

CARD_ECC_FAILED

CC_ERROR

N/A

E R

Not used with SDIO operation

A general or an unknown error

occurred during the operation.

Not used with SDIO operation

ERROR

’0’= no error

’1’= error

12:9

UNDERRUN

N/A

S X

OVERRUN

CID/ CSD_OVERWRITE

WP_ERASE_SKIP

CARD_ECC_DISABLED

ERASE_RESET

Not used with SDIO operation

For an I/O only card, the current

state shall be fixed at a value of

0x0F. This indicates that it is an I/O

only card and the normal memory

states do not apply

CURRENT_STATE

15=I/O only

7:6

READY_FOR_DATA

Reserved

APP_CMD

N/A

Not used with SDIO operation

CMD55 not used in SDIO operation

Not used with SDIO operation

Reserved

AKE_SEQ_ERROR

(SD N/A

Memory Card app. spec.)

1, 0

Reserved for application specific commands

Reserved for manufacturer test mode

Table 4-7 SDIO Status Register Structure

Note 1: In the SPI mode, if the card detects a CRC error, it returns a com CRC error in the R1 response

immediately following the command (see Figure 3-7). In this situation, the note that the CRC error is for the

previous command does not apply.

Note 2: In the SPI mode, if the card detects an Illegal Command, it returns an Illegal Command error in the R1

response immediately following the command (see Figure 3-7). In this situation, the note that the Illegal

Command error is for the previous command does not apply.

SDIO Simplified Specification Version 2.00

5. New I/O Read/Write Commands

Two additional data transfer instructions have been added to support I/O. IO_RW_DIRECT, a direct I/O

command similar to the MMC 'Fast I/O' command, and IO_RW_EXTENDED, which allows fast access with byte

or block addresses. Both commands are in class 9 (I/O Commands).

5.1

IO_RW_DIRECT Command (CMD52)

The IO_RW_DIRECT is the simplest means to access a single register within the total 128K of register space in

any I/O function, including the common I/O area (CIA). This command reads or writes 1 byte using only 1

command/response pair. A common use is to initialize registers or monitor status values for I/O functions. This

command is the fastest means to read or write single I/O registers, as it requires only a single

command/response pair.

S D Command R/W

Function

Number

RAW Stuff

flag

Stuff

Write Data

or Stuff Bits

CRC7

Index

110100b

flag

1 1

Figure 5-1 IO_RW_DIRECT Command

The IO_RW_DIRECT Command contains the following fields:

S(tart bit):

Start bit. Always 0

D(irection):

Command Index:

R/W Flag:

Direction. Always1 indicates transfer host to card.

Identifies the “IO_RW_DIRECT” command with a value of 110100b

This bit determines the direction of the I/O operation. If this bit is 0, this command

shall read data from the SDIO card at the address specified by the Function Number

and the Register Address to the host. The data byte is returned in the response, R5.

If this bit is set to 1, the command shall write the bytes in the Write Data field to the

I/O location addressed by the Function Number and the Register Address. If the

RAW flag is 0, then the data in the register that was written shall be read and that

value returned in the response.

RAW Flag:

The Read after Write flag. If this bit is set to 1 and the R/W flag is set to 1, then the

command shall read the value of the register after the write. This is useful to allow

writing to a control register and reading the status at the same address. If this bit is

cleared, the value returned in the R5 response shall be the same as the write data in

the command. If this bit is set, the data field of the R5 response shall contain the

value read from the addressed register after the write operation.

The number of the function within the I/O card you wish to read or write. Note that

function 0 selects the common I/O area (CIA).

Function Number:

This is the address of the byte of data inside of the selected function to read or write.

There are 17 bits of address available so the register is located within the first 128K

(131,072) addresses of that function.

Write Data/Stuff Bits:

For a direct write command (R/W=1), this is the byte that is written to the selected

address. For a direct read (R/W=0), this field is not used and shall be set to 0.

7 bits of CRC data

CRC7:

E(nd bit):

End bit, always 1

SDIO Simplified Specification Version 2.00

5.2

IO_RW_DIRECT Response (R5)

The SDIO card’s response to CMD52 shall be in one of two formats. If the communication between the card and

host is in the 1-bit or 4-bit SD mode, the response shall be in a 48-bit response (R5) as described in 5.2.1. If the

communication is using the SPI mode, the response shall be a 16-bit R5 response as described in 5.2.2.

5.2.1

CMD52 Response (SD modes)

The SDIO card’s response to CMD52 in the SD mode is shown in Figure 5-2. If the operation was a read

command, the data being read is returned as an 8-bit value. In addition, 15 bits of status information is returned.

The format of the SD response is as follows:

S D Command

Index

Stuff

Response Flags

Read or Write

Data

CRC7

Bit

110100b

7--------------------------0

1 1

Figure 5-2 R5 IO_RW_DIRECT Response (SD modes)

The IO_RW_DIRECT response (R5) contains the following fields:

S(tart bit):

Start bit. Always 0

D(irection):

Command Index:

Stuff Bits

Direction. 0 indicates transfer card to host (Response)

Identifies the “IO_RW_DIRECT” command with a value of 110100b

Not used, shall be set to 0

Response Flags

8 Bits of flag data indicating the status of the SDIO card. Table 5-1 shows the format

of these flag bits.

Read or Write Data:

For an I/O write (R/W=1) with the RAW Flag set (RAW=1) this field shall contain the

value read from the addressed register after the write of the data contained in the

command. Note that in this case, the read-back data may not be the same as the

data written to the register, depending on the design of the hardware. For an I/O

write with the RAW bit=0, the SDIO function shall not do a read after write operation,

and the data in this field shall be identical to the data byte in the write command. For

an I/O read (R/W=0), the actual value read from that I/O location is returned in this

field.

CRC7:

7 bits of CRC data

E(nd bit):

End bit, always 1

Bits

Identifier

Type

E R

Value

Description

Clear

Condition

COM_CRC_ERROR

ILLEGAL_COMMAND

’0’= no error The CRC check of the previous

’1’= error command failed.

’0’= no error Command not legal for the card

’1’= error State.

E R

SDIO Simplified Specification Version 2.00

Bits

Identifier

Type

Value

00=DIS

Description

DIS=Disabled:

Clear

Condition

5-4

IO_CURRENT_STATE

01=CMD

02=TRN

03=RFU

Initialize, Standby and Inactive

States (card not selected)

CMD=DAT lines free:

1. Command waiting (No

transaction suspended)

2. Command waiting (All

CMD53 transactions

suspended)

3. Executing CMD52 in CMD

State

TRN=Transfer:

Command executing with data

transfer using DAT[0] or DAT[3:0]

lines

ERROR

E R

’0’= no error A general or an unknown error

E R X ’1’= error

occurred during the operation.

Type “E R” shall be used for

CMD52

Type “E R X” shall be used for

CMD53

RFU

Fixed at 0

Reserved for Future Use

FUNCTION_NUMBER E R

’0’= no error An invalid function number was

’1’= error requested

’0’= no error The command’s argument was out

’1’= error of the allowed range for this card.

OUT_OF_RANGE

E R

Table 5-1 Flag data for IO_RW_DIRECT SD Response

5.2.2

R5, IO_RW_DIRECT Response (SPI mode)

The SDIO card’s response to CMD52 in the SPI mode is shown in Figure 5-3. If the operation was a read

command, the data being read is returned as an 8-bit value. In addition, 8 bits of status information is returned in

a SPI R1 response byte as described in Fig 47 of the SD Physical Specification modified for I/O as shown in

Figure 5-3.

R/W Data (8 Bits)

1 = in idle state

RFU (always 0)

1 = illegal command

1 = COM CRC error

1 = Function number error

RFU (always 0)

1 = parameter error

Start Bit (always 0)

Figure 5-3 IO_RW_DIRECT Response in SPI Mode

Note the read/write (R/W) data is identical to the read/write data described for the SD R5 response (see 5.2.1).

Parameter error status in SPI mode corresponds to OUT_OF_RANGE and ERROR in the SD mode response.

In the case of CMD53, Data Error Token should also be used to indicate OUT_OF_RANGE and ERROR.

SDIO Simplified Specification Version 2.00

5.3

IO_RW_EXTENDED Command (CMD53)

In order to read and write multiple I/O registers with a single command, a new command, IO_RW_EXTENDED

is defined. This command is included in command class 9 (I/O Commands). This command allows the reading

or writing of a large number of I/O registers with a single command. Since this is a data transfer command, it

provides the highest possible transfer rate.

S D Command

Index

R/W Function Block

flag Number Mode Code

Byte/Block

Count

CRC

110101b

1 1

Figure 5-4 IO_RW_EXTENDED Command

The IO_RW_EXTENDED Command contains the following fields:

S(tart bit):

Start bit. Always 0

D(irection):

Command Index:

R/W Flag:

Direction. Always1 indicates transfer host to card.

Identifies the “IO_RW_EXTENDED” command with a value of 110101b

This bit determines the direction of the I/O operation. If this bit is 0, this command

reads data from the SDIO card at the address specified by the Function Number and

the Register Address to the host. The read data shall be returned on the DAT[x]

lines. If this bit is set to 1, the command shall write the bytes from the DAT[x] lines to

the I/O location addressed by the Function Number and the Register Address.

The number of the function within the I/O card you wish to read or write. Note that

function 0x00 selects the common I/O area (CIA).

(Optional) this bit, if set to 1, indicates that the read or write operation shall be

performed on a block basis, rather than the normal byte basis. If this bit is set, the

Byte/Block count value shall contain the number of blocks to be read/written. The

block size for functions 1-7 is set by writing the block size to the I/O block size

by writing to the FN0 Block Size register in the CCCR. Card and host support of the

block I/O mode is optional. The host can determine if a card supports block I/O by

reading the Card supports MBIO bit (SMB) in the CCCR (see Table 6-2). The block

size used when Block Mode = 1 and the maximum byte count per command used

Function Number:

Block Mode

when Block Mode

can be read from the CIS in the tuple

TPLFE_MAX_BLK_SIZE (see 16.7.4) on a per-function basis.

Defines the read/write operation as described in Table 5-2

OP code

Command operation

Multi byte R/W to fixed address

Multi byte R/W to incrementing address

Table 5-2 IO_RW_ EXTENDED command Op Code Definition

• OP Code 0 is used to read or write multiple bytes of data to/from a single I/O register

address. This command is useful when I/O data is transferred using a FIFO inside of

the I/O card. In this case, multiple bytes of data are transferred to/from a single

for SD memory cards.

• OP Code 1 is used to read or write multiple bytes of data to/from an I/O register

SDIO Simplified Specification Version 2.00

address that increment by 1 after each operation. This command is used when large

amounts of I/O data exist within the I/O card in a RAM like data buffer. In this

operation, the start address is loaded into the Register Address field. The first

operation occurs at that address within the I/O card. The next operation shall occur

at address+1 with the address incrementing by 1 until the operation has completed.

As with OP Code 0, the number of bytes is set in the Byte Count field of the

command.

Byte/Block Count

Start Address of I/O register to read or write. Range is [0x1FFFF:0]

If the command is operating on bytes (Block Mode = 0), this field contains the

number of bytes to read or write. A value of 0x000 shall cause 512 bytes to be read

or written.

Count Value

Bytes Transferred

Block Transferred

0x000

512

∞

0x001

0x002 ----

0x1FF

511

Table 5-3 Byte Count Values

If the command is in block mode (Block Mode=1), the Block Count field specifies the

number of Data Blocks to be transferred following this command. A value of 0x000

indicates that the count set to infinite. In this case, the I/O blocks shall be transferred

until the operation is aborted by writing to the I/O abort function select bits (ASx) in

the CCCR (see Table 6-1 and Table 6-2). Table 5-3 shows the relationship between

the value in the command and the actual number of bytes transferred.

7 bits of CRC data

CRC7:

E(nd bit):

End bit, always 1

The response from the SDIO card to CMD53 shall be R5 (the same as CMD52) as defined in 5.2. For CMD53,

the 8-bit data field shall be stuff bits and shall be read as 0x00. Also, the ERROR response bit shall be type “E R

X” (see Table 5-1).

5.3.1

CMD53 Data Transfer Format

When executing the IO_RW_EXTENDED (CMD53), the multi-byte or multi-block data transfer is similar to the

data transfer for memory. For the multi-byte transfer modes (block mode=0) the following applies:

IO_RW_EXTENDED byte read is similar to CMD17 (READ_SINGLE_BLOCK)

IO_RW_EXTENDED byte write is similar to CMD24 (WRITE_BLOCK)

Note that the byte count for this transfer is set in the command, rather than the fixed block size. Thus, the size of

the data payload is in the range of 1-512 bytes. The block mode is similar to the following memory commands:

IO_RW_EXTENDED block read is similar to CMD18 (READ_MULTIPLE_BLOCK)

IO_RW_EXTENDED block write is similar to CMD25 (WRITE_MULTIPLE_BLOCK)

For the block mode the only difference is that for a fixed block count, the host does not need to stop the transfer,

as it continues until the block count is satisfied. If the block count is set to zero, the operation is identical to the

memory mode in that the host must stop the transfer.

5.3.2

Special Timing for CMD53 Multi-Block Read

This section is not included in the Simplified Specification.

SDIO Simplified Specification Version 2.00

6. SDIO Card Internal Operation

I/O access differs from memory in that the registers can be written and read individually and directly without a

FAT file structure or the concept of blocks (although block access is supported). These registers allow access to

the I/O data, control of the I/O function and report on status or transfer I/O data to/from the host. The SD memory

relies on the concept of a fixed block length with commands reading/writing multiples of these fixed size blocks.

I/O may or may not have fixed block lengths and the read size may be different from the write size. Because of

this, I/O operations may be based on either a length (byte count) or a block size.

6.1

Overview

Each SDIO card may have from 1 to 7 functions plus one memory function built into it. A function is a self

contained I/O device. I/O functions may be identical or completely different from each other. All I/O functions are

organized as a collection of registers. There is a maximum of 131,072 (2¹⁷) registers possible for each I/O

function. These registers and their individual bits may be read Only (RO), Write Only (WO) or Read/Write (R/W).

These registers can be 8, 16 or 32 bits wide within the card. All addressing is based on byte access. These

registers can be written and/or read one at a time, multiply to the same address or multiply to an incrementing

address. The single R/W access is often used to initialize the I/O function or to read a single status or data value.

The multiple reads to a fixed address are used to read or write data from a data FIFO register in the card. The

read to incrementing addresses is used to read or write a collection of data to/from a RAM area inside of the

card. Figure 6-1 shows the mapping of the CIA and optional CSA space for an SDIO card.

6.2

All registers in SDIO only cards and the SDIO portion of Combo cards shall complete read and write data

transfer in less than 1 second. This timeout value relates to the time for the requested data to be transferred

to/from the host on the DAT[x] lines and not the timing between the command and the response. This wait time

is signaled to the host by the card using busy for a write or delaying the start bit for a read operation. The host

can use 1 second as the timeout value for a non-responding location. If a functions needs to support an access

time greater than 1 second, the card maker may use some function specific method that is not defined in this

specification.

6.3

Interrupts

All SDIO hosts should support hardware interrupts. If a host does not support interrupts, it may have difficulties

working with SDIO cards that expect fast response to interrupt conditions. Each function within an SDIO or

Combo card may implement interrupts as needed. The interrupt used on SDIO functions is a type commonly

called “level sensitive”. Level sensitive means that any function may signal for an interrupt at any time, but once

the function has signaled an interrupt, it shall not release (stop signaling) the interrupt until the cause of the

interrupt is removed or commanded to do so by the host. Since there is only 1 interrupt line, it may be shared by

multiple interrupt sources. The function shall continue to signal the interrupt until the host responds and clears

the interrupt. Since multiple interrupts may be active at once, it is the responsibility of the host to determine the

interrupt source(s) and deal with it as needed. This is done on the SDIO function by the use of two bits, the

interrupt enable and interrupt pending. Each function that may generate an interrupt has an interrupt enable bit.

In addition, the SDIO card has a master interrupt enable that controls all functions. An interrupt shall only be

signaled to the SD bus if both the function’s enable and the card’s master enable are set. The second interrupt

bit is called interrupt pending. This read-only bit tells the host which function(s) may be signaling for an interrupt.

There is an interrupt pending bit for each function that can generate interrupts. These bits are located in the

CCCR area. For more details, see Table 6-1 and Table 6-2. Interrupt operation is described more fully in section

SDIO Simplified Specification Version 2.00

6.4

Suspend/Resume

Within a multi-function SDIO or a Combo card, there are multiple devices (I/O and memory) that share access to

the SD bus. In order to allow the sharing of access to the host among multiple devices, SDIO and combo cards

can implement the optional concept of suspend/resume. If a card supports suspend/resume, the host may

temporarily halt a data transfer operation to one function or memory (suspend) in order to free the bus for a

higher priority transfer to a different function or memory. Once this higher-priority transfer is complete, the

original transfer is re-started where it left off (resume). Support of suspend/resume is optional on a per-card

basis. If suspend/resume is implemented, it shall be supported by the memory (if any) of a Combo card and all

I/O functions except 0 (the CIA). Note that the host can suspend multiple transactions and resume them in any

order desired. I/O function 0 does not support suspend/resume. Suspend/Resume is described in more detail in

section 9. Any card that supports Suspend/Resume shall also support Read Wait and Direct Commands (SRW

and SDC = 1) Note that Suspend/Resume is defined only for the SD 1 and 4-bit modes. It does not apply to SPI

transfers.

6.5

Read Wait

Host devices built to the SD Physical Specification shall control the SDCLK to stop the read data block output

from a card executing a multiple read command whenever the host cannot accept more data. During the time

that the host has stopped the SDCLK, a CMD52 cannot be issued. This limitation causes a problem in that a

host device built to the SD Physical Specification cannot perform the I/O command during a multiple read cycle.

In order to eliminate this limitation, the SDIO Specification adds the Read Wait control to enable the host to issue

CMD52 during a multiple read cycle. Read Wait uses the DAT[2] line to allow the host to signal the card to

temporarily halt the sending of read data by a card. This feature is optional for an SDIO or combo card. However,

if an SDIO or combo supports Read Wait, all functions and any memory shall support Read Wait. Read Wait is

described in more detail in section 10. Any card that supports Suspend/Resume shall also support Read Wait.

Note that Read Wait is defined only for the SD 1 and 4-bit modes. It does not apply to SPI transfers.

6.6

CMD52 During Data Transfer

A card may accept CMD52 during data transfer if it supports Direct Commands (see SDC, Table 6-3). For both SD

and SPI modes, if an error occurs during data transfer the SDIO card shall accept CMD52 to allow I/O abort and

reset regardless of this bit value of the value of SDC.

6.7

SDIO Fixed Internal Map

The SDIO card has a fixed internal register space and a function unique area. The fixed area contains

information about the card and certain mandatory and optional registers in fixed locations. The fixed locations

allow any host to obtain information about the card and perform simple operations such as enable in a common

manner. The function unique area is a per-function area, which is defined either by the Application

Specifications for Standard SDIO functions or by the vendor for non-standard functions. Figure 6-1 shows the

internal map of an SDIO card with multiple functions.

SDIO Simplified Specification Version 2.00

CIA (Function 0)

0x000000-0x0000FF

CCCR

Window

0x000100-0x0001FF FBR (Function 1)

0x000200-0x0002FF FBR (Function 2)

0x000300-0x0003FF FBR (Function 3)

16 MB optional

Code Storage

Area

Window

0x000700-0x0007FF FBR (Function 7)

RFU

0x000800-0x000FFF

CIS Area

(common and per-function)

(CSA)

0x001000-0x017FFF

CIS Pointers

RFU

0x018000-0x01FFFF

128K Register Space

(function 1-7)

0x000000-0x01FFFF

Function Unique

Figure 6-1 SDIO Internal Map

6.8

Common I/O Area (CIA)

The Common I/O Area (CIA) shall be implemented on all SDIO cards. The CIA is accessed by the host via I/O

reads and writes to function 0. The registers within the CIA are provided to enable/disable the operation of the

I/O function(s), control the generation of interrupts and optionally load software to support the I/O functions. The

registers in the CIA also provide information about the function(s) abilities and requirements. There are three

distinct register structures supported within the CIA. They are:

1. Card Common Control Registers (CCCR)

2. Function Basic Registers (FBR)

3. Card Information Structure (CIS)

6.9

Card Common Control Registers (CCCR)

The Card Common Control Registers allow for quick host checking and control of an I/O card’s enable and

interrupts on a per card (master) and per function basis. The bits in the CCCR are mixed Read/Write and read

only. If any of the possible 7 functions are not provided on an SDIO card, the bits corresponding to unused

functions shall all be read-only and read as 0. All reserved for future use bits (RFU) shall be read-only and return

a value of 0. All writeable bits are set to 0 after power-up or reset. Access to the CCCR is possible even after

initialization when the I/O functions are disabled. Access is performed using the I/O read and write commands

defined in section 5. This allows the host to enable functions after initialization. The CCCR is organized as

follows:

SDIO Simplified Specification Version 2.00

Address Register Name

Bit 7

SDIO

bit 3

Bit 6

SDIO

bit 2

Bit 5

SDIO

bit 1

Bit 4

SDIO

bit 0

Bit 3

Bit 2

Bit 1

Bit 0

CCCR CCCR CCCR CCCR

bit 3

0x00

CCCR/SDIO

Revision

bit 2

bit 1

bit 0

RFU

0x01

SD Specification

Revision

bit 3

bit 2

IOE2

IOR2

IEN2

INT2

AS2

RFU

bit 1

IOE1

IOR1

IEN1

INT1

AS1

Bus

bit 0

RFU

IENM

RFU

AS0

Bus

IOE7

IOR7

IEN7

INT7

RFU

Disable

4BLS

IOE6

IOR6

IEN6

INT6

RFU

SCSI

IOE5

IOR5

IEN5

INT5

RFU

ECSI

IOE4

IOR4

IEN4

INT4

RFU

IOE3

IOR3

IEN3

INT3

RES

RFU

0x02

0x03

0x04

I/O Enable

I/O Ready

Int Enable

0x05

Int Pending

I/O Abort

Bus Interface

Control

0x06

0x07

Width 1 Width 0

LSC

E4MI

S4MI

SBS

SRW

SMB

SDC

0x08

0x09-

0x0B

0x0C

0x 0D

0x 0E

0x 0F

0x10-

0x11

Card Capability

Common CIS

Pointer

Bus Suspend

Function Select

Exec Flags

Ready Flags

FN0 Block Size

Pointer to card’s common Card Information Structure (CIS)

RFU

EX7

RF7

RFU

EX6

RF6

RFU

EX5

RF5

RFU

EX4

RF4

RFU

FS3

EX3

RF3

RFU

FS2

EX2

RF2

FS1

EX1

RF1

FS0

EXM

RFM

I/O block size for Function 0

Reserved for Future Use (RFU)

RFU RFU RFU RFU

EMPC SMPC

EHS SHS

0x 12

0x 13

0x14-

0xEF

0xF0-

0xFF

Power Control

High-Speed

RFU

Reserved for Future Use (RFU)

Area Reserved for Vendor Unique Registers

Reserved for

Vendors

Table 6-1 Card Common Control Registers (CCCR)

Field

Type

Description

CCCRx

R/O

CCCR Format Version number. These 4 bits contain the version of the CCCR and

FBR format that this card supports. Any change to the CCCR and/or the FBR

structure shall cause a new version code to be assigned. The codes for the

CCCR/FBR formats are as follows:

Value

0x00

0x01

0x02

CCCR/FBR Format Version

CCCR/FBR Version 1.00

CCCR/FBR Version 1.10

CCCR/FBR Version 1.20

Reserved for Future Use

0x03-0x0F

SDIOx

R/O

SDIO Specification Revision number. These 4 bits contain the version of the SDIO

Specification that this card supports. The codes for the SDIO Specifications are as

follows:

Value

0x00

0x01

0x02

0x03

SDIO Specification

SDIO Specification Version 1.00

SDIO Specification Version 1.10

SDIO Specification Version 1.20 (unreleased)

SDIO Specification Version 2.00

Reserved for Future Use

0x04-0x0F

SDIO Simplified Specification Version 2.00

Field

Type

Description

SDx

R/O

SD Format Version number. These 4 bits contain the version of the SD Physical

Specification that this card supports. The codes for the SD Physical Specification are

as follows:

Value

SD Physical Specification

0x00

0x01

0x02

0x03-0x0F

SD Physical Specification Version 1.01 (March 2000)

SD Physical Specification Version 1.10 (October 2004)

SD Physical Specification Version 2.00 (May 2006)

Reserved for Future Use

IOEx

IORx

R/W

Enable Function - If this bit is reset to 0, the function is disabled. If this bit is set to 1,

the function is enabled to start its initialization. The completion of initialization is

indicated in IORx. On power up or after a reset, the card shall reset this bit to 0. The

host can also use IOEx as a per function reset for error recovery. The host sequence

for a per function reset is to reset IOEx to 0, wait until IORx becomes 0 and then set

IOEx to 1 again. If the error is not recovered by this sequence, SDIO reset should be

used noting that the operation of all functions will be aborted. See section 11 for

relation to Master Power Control and Power Select.

I/O Function Ready- If this bit is reset to 0, the function is not ready to operate. This

may be caused by the function being disabled or not ready due to internal causes

such as a built-in self-test in progress. If this bit is set to 1, the function is ready to

operate. The functions shall set this bit to 1 within the timeout value defined in the

TPLFE_ENABLE_TIMEOUT_VAL tuple. On power up or after a reset, this bit shall

be set to 0. For any function that is not implemented on an SDIO card, this bit shall

always be 0.

R/O

IENx

IENM

INTx

R/W

R/O

Interrupt Enable for function x. If this bit is cleared to 0, any interrupt from this function

shall not be sent to the host. If this bit is set to 1, then this function’s interrupt shall be

sent to the host if the master Interrupt Enable (bit 0) is also set to 1.

Interrupt Enable Master. If this bit is cleared to 0, no interrupts from this card shall be

sent to the host. If this bit is set to 1, then any function’s interrupt shall be sent to the

host.

Interrupt Pending for function x. If this bit is cleared to 0, this indicates that no

interrupts are pending from this function. If this bit is set to 1, then this function has

interrupt pending. Note that if the IENx or IENM bits are not set, the host cannot

receive this pending interrupt.

ASx

W/O

Abort Select In order to abort an I/O read or write and free the SD bus, the function

that is currently transferring data must be addressed. These 3 bits define which

function’s transfer to stop. For example, the abort the transfer to function number 3,

the value of 0x03 would be written to these bits using CMD52 only. If the abort is

addressed to a suspended function, it does not affect current data transaction. Note

that this is an abort, not a reset. The addressed function shall return to the CMD state

and data transfer pending to that function shall be halted. This abort procedure does

not work for SPI write operations. To abort an SPI write data transfer use the

STOP_TRAN token as defined in section 7.3.3 of the SD Physical Specification. This

form of abort applies only to the functions of an SDIO card. For the memory of a

combo card, the abort methods defined in the SD Physical Specification shall be used

to abort transfers to/from memory

W/O

I/O CARD RESET: Setting the RES to 1 shall cause all I/O functions in an SDIO or

Combo card to perform a soft reset. Setting the RES to 1 does not affect the current

card protocol selection(SD vs. SPI mode) and CD Disable. Setting of the RES bit

shall only be performed using CMD52. When RES=1, the values of AS2-0 are

don’t-cares. The RES bit is auto cleared, so there is no need to rewrite a value of 0.

This bit is write-only, any read returns an undetermined value. Memory in a combo

card is not affected.

RES

SDIO Simplified Specification Version 2.00

Field

Bus Width

1:0

Type

R/W

Description

Defines the data bus width (’00’=1-bit or’10’=4-bit bus) to be used for data transfer. All

Full-Speed SDIO cards support both 1 and 4-bit bus. A Low-Speed SDIO card’s

support of 4-bit bus is optional. On reset or power-on these bits are cleared to 00.

Connect[0]/Disconnect[1] the 10K-90K ohm pull-up resistor on CD/DAT[3] (pin 1) of

the card. The pull-up may be used for card detection. This bit is cleared to 0 on

power-on (connected). Its state is not affected by a reset command.

Support Continuous SPI interrupt. This read-only bit is set to indicate that this SDIO

card supports the assertion of interrupts in the SPI mode at any time, irrespective of

the status of the card select (CS) line. If this bit is zero, then this SDIO card can only

assert the interrupt line in the SPI mode when the CS line is asserted. This bit signals

the capability of all functions in the SDIO card.

CD Disable

SCSI

R/W

R/O

ECSI

SDC

R/W

R/O

Enable Continuous SPI Interrupt. If the SCSI bit is set, then this R/W bit is used to

allow the SDIO card to assert the interrupt line in the SPI mode at any time,

irrespective of the state of the CS line. This bit is cleared to zero on reset or power-up.

If the SCSI bit is clear, this bit shall be read only and set to zero. This bit controls the

assertion of interrupts in the SPI mode for all functions in the SDIO card.

Card Supports Direct Commands during data transfer. This bit applies only to the SD

modes, it does not apply to SPI mode. This flag bit reports the SDIO card’s ability to

execute CMD52 while data transfer is in progress. If this bit is set, all I/O functions

shall accept and execute the CMD52 while data transfer is underway on the DAT[x]

lines. Also, any memory in a combo card shall allow the CMD52 to execute while it is

transferring data. Since the CMD52 does not use the DAT[x] lines, it is possible to

execute while data transfer to a different address on the card is underway. CMD52 is

described in 5.1. In any case, SD or SPI mode, if an error occurs during data transfer

the SDIO card shall accept CMD52 to allow I/O abort and reset regardless of this bit

value. If the card supports suspend/resume then it shall also support this bit.

Card Supports Multi-Block. This flag bit reports the SDIO card’s ability to execute the

IO_RW_EXTENDED command (CMD53) in the block mode. If this bit is set, all I/O

functions (0-7) shall accept and execute CMD53 with the optional block mode bit set.

The IO_RW_EXTENDED command is described in 5.3

SMB

SRW

R/O

Card Supports Read Wait. This bit applies only to the SD modes, it does not apply to

SPI mode. This flag bit reports the SDIO card’s ability to support the Read Wait

Control (RWC) operation. If set, all functions on the card are able to accept the wait

signal on DAT[2]. RWC operation is described in section 6.5. Any card that supports

Suspend/Resume shall also support Read Wait

SBS

R/O

Card supports Suspend/Resume. This bit applies only to the SD modes, it does not

apply to SPI mode. This flag bit reports the SDIO card’s ability to Suspend and

Resume operations at the request of the host. If this bit is set, all functions except 0

shall accept a request to suspend operations and resume under host control.

Suspend/Resume operation is described in 6.4. If this bit is 0, registers (0x0C-0x0F)

shall not be supported.

Supports interrupt between blocks of data in 4-bit SD mode. This flag bit reports the

SDIO card’s ability to generate interrupts during a 4-bit multi-block data transfer. If

this bit is 0, then the SDIO card is not able to signal an interrupt during a multi-block

data transfer in 4-bit mode. In this case, the interrupt is not signaled until after the

data transfer is complete. If this bit is 1, then the SDIO card is able to signal an

interrupt between blocks while data transfer is in progress. This operation is

described in 8.1.4 Note, even if a card does not support the interrupt during 4-bit

block transfer (S4MI=0), the card may signal interrupts during all other Interrupt

Periods while the interrupt is enabled (IENx=1).

S4MI

SDIO Simplified Specification Version 2.00

Field

Type

Description

E4MI

R/W

Enable interrupt between blocks of data in 4-bit SD mode. Enable the multi-block IRQ

during 4-bit transfer for the SDIO card. When this bit is 0, the card shall not signal

interrupts during a 4-bit multi-block data transfer. If this bit is 1, the card shall generate

interrupts during 4 bit multi-block data transfers as described in 8.1.4 If this SDIO card

does not support 4 bit multi-block IRQs (S4MI=0), then this bit shall be R/O and

always read as 0. This bit shall be cleared to 0 by any reset

LSC

R/O

Card is a Low-Speed card. If this bit is set, it indicates that the SDIO card is a

Low-Speed card (see 2.1). If this bit is clear, the SDIO card is a Full-Speed card.

4-bit support for Low-Speed cards. If the SDIO card is a Low-Speed card (LSC=1)

and it supports 4-bit data transfer, then this bit shall be set. If the card is not

Low-Speed or if the card does not support 4-bit transfer, then this bit shall be zero.

This 3-byte pointer points to the start of the card’s common CIS. The common CIS

contains information relation to the entire card. The card common CIS shall be

located within the CIS space of function 0 (0x001000- 0x017FFF) as described in

section 6.11. A card common CIS is mandatory for all SDIO cards. This pointer is

stored in little-endian format (LSB first).

Bus status: If this bit is set to 1, then the currently addressed function (selected by

FSx or by the function number in an I/O command) is currently executing a command

which transfers data on the DAT[x] line(s). If this bit is 0, then the addressed function

is not using the data bus. This bit is used by the host to determine which function of a

multi-function or combo card is currently performing data transfer. Note that this bit is

a part of the optional Suspend/Resume protocol. If the card does not support

Suspend/Resume, this bit shall be read as 0. Any access to the CIA may not be

suspended, so in this case, BS shall always be set to 1, irrespective of the host

setting BR to 1.

4BLS

Pointer to

card’s

common CIS

R/O

R/W

Bus Release Request/Status: This bit is used to request that the addressed function

(selected by FSx or by the function number in CMD53 or Memory commands using

DAT line) release the Data lines and suspend operation. If the host sets this bit to 1,

the addressed function shall temporarily halt data transfer on the DAT[x] lines and

suspend the command that is in process. The BR bit shall remain set to 1 until the

release is complete. If the card can never accept the suspend request while

executing transactions, the card shall return response with BR cleared to 0 and BS

set to 1. This indicates that the suspend request is cancelled by the card and thus the

host should not issue a cancel suspend command.

The followings are the cases where the card can cancel a suspend request:

Transaction addressed to function 0.

The card knows the transfer will terminate soon.

The card knows the transfer is timing critical (i.e. If suspended, the transfer cannot

proceed).

A Multi function card that indicates SBS=1, but contains a function that does not

support suspend/resume.

Once the function is in suspend, it shall signal the host by clearing the BS and BR

bits. The host can monitor the status of the suspend request by reading the BR bit. If

it is set, the suspend request is still in progress. A pending suspend request can be

cancelled by the host by writing 0 to the BR bit.

The Standard Host Specification defines following suspend sequence:

If the suspend request is not accepted, the host retries with a cancel suspend request

command. Even if the card received a cancel suspend command, it should accept

suspend if possible. If the card does not accept suspend, the host considers the

function to have never suspend.

However, the host should monitor the BR, BS and EXx bits to confirm that the

suspend request was cancelled rather that granted. If SBS=0, this bit shall be R/O

and read as 0.

SDIO Simplified Specification Version 2.00

Field

Type

Description

FSx

R/W

Select Function bits 3:0 These four bits are used to select a function number (0-7) or

the memory of a combo card (8) for Suspend/Resume. There are 2 means to write

the value of FSx. First, an I/O writes to the register in the CCCR and second, a new

I/O command causes the FSx to be set to the function number in that command. The

value of FSx shall remain until overwritten. If a function or memory is currently

suspended, the writing of it’s number to FSx shall re-start (resume) the data transfer

operation When reading FSx, the value returned shall be the number of the currently

addressed function. Note that when reading FSx, if the Bus Status is 0 (BS=0), the

FSx value is undefined. The FSx bits are coded as follows:

FSx

0000

0001-0111

1000

Current Transaction

Transaction of function 0 (CIA)

Transaction to functions 1-7

Transaction of memory in combo card

Not defined, reserved for future use

1001-1111

If SBS=0 these bits shall be R/O.

R/O

Resume Data Flag: A data transaction is resumed by writing its number to FSx. Once

the transaction is resumed, the DF indicates if more data will be transferred. If DF is

cleared to 0, then no additional data will be transferred after the function or memory is

resumed. If DF is set to 1, then there is more data to transfer that will begin after the

function or memory in resumed. The DF flag can be used to control the interrupt cycle

in 4-bit mode. If DF=1, there is more data to transfer after restoring the function. In

this case, the interrupt cycle should be disabled. If DF=0, the function or memory was

suspended at end of data transfer (during busy). In this case, no data transfer shall

begin after resume so the host can detect a start interrupt cycle after restore. When

resuming, if the suspended function cannot continue data transfer the card shall

return DF=0 to abort the transfer.

EXx

RFx

R/O

Execution Flag bits 7:0 These bits are used by the host to determine the current

execution status of all functions (1-7) and memory (0). The bit is set to 1 for each

function or memory that is currently executing a command. The EXx bits tell the host

that a function or memory is currently executing a command so no additional

command should be issued to that function/memory. These bits are only defined if

SBS=1. This bit is set if the function is active (either currently executing or

suspended). If SBS=0 these bits shall be read as zero.

Ready Flag bits 7:0 These bits tell the host the read or write busy status for functions

(1-7) and memory (0). If a function or memory is executing a write transaction, an RFx

bit cleared to 0 indicates the function/memory is busy and not ready to accept more

data. If the RFx bit is set to 1, then the function/memory can accept write data. If a

function/memory is executing a read command, if the RFx bit is cleared to 0, it

indicates that read data is NOT available. If the bit is set to 1, it indicates that read

data is ready to be transferred. These bits are only defined if SBS=1. Setting a bit to 1

indicates the function is ready to accept the resume command. There are two

conditions where the function will set the bit to 1. One is when the function (executing

or suspended) is ready to continue data transfer. The other is when the suspended

function cannot continue data transfer. If SBS=0 these bits shall be read as zero.

This 16-bit register sets the block size for I/O block operations for Function 0 only. If

this card does not support I/O block operations (SMB=0), then this register becomes

read-only and shall always read 0x0000. The maximum block size is 2048 (0x0800)

and the minimum is 1. At power-up or reset, this register shall be initially loaded with a

value of 0x0000. The host is responsible for setting the appropriate value for the

block size supported by function 0. This pointer is stored in little-endian format (LSB

first).

FN0 Block

Size

R/W

SDIO Simplified Specification Version 2.00

Field

Type

Description

SMPC

R/O

Support Master Power Control These bits tell the host if the card supports Master

Power Control.

SMPC=0 : The total card current is less than 200mA, even if all functions

are active (IOEx=1). EMPC,SPS and EPS shall be zero.

SMPC=1 :The total card current may exceed 200mA.

EMPC, SPS and EPS are available.

EMPC

R/W

Enable Master Power Control

EMPC=0(default): The total card current shall be less than 200mA.

The card automatically switches the mode of function(s) to lower current or does not

allow some functions to become enabled, regardless of the value of EPS, so that total

card current is 200mA or less. (The card manufacturer determines which functions

operate and their modes to guarantee this limit.)

EMPC=1: The total card current may exceed 200mAand SPS and EPS are available.

The host uses SPS, EPS in FBR and IOEx to enable higher current function modes

based on the host’s ability to supply the necessary current.

Support High-Speed

This flag bit reports the card’s ability to operate in High-Speed mode

SHS=0: The card does not support High-Speed mode

SHS=1: The card supports High-Speed mode. The host enables High-Speed mode

via the EHS bit. See section 12 for details on switching between default and

High-Speed mode.

SHS

EHS

R/O

R/W

Enable High-Speed

EHS=0 (default): The card operates in default timing mode with a clock rate up to

25MHz.

EHS=1 : High-Speed Mode

The card operates in High-Speed timing mode with a clock rate up to 50MHz. See

section 12 for details on switching between default and High-Speed mode.

When SHS is set to 0, writing to this bit is ignored and always indicates 0.

Any bit defined as Reserved for Future Use (RFU) shall be read-only and shall be

read as 0.

These 16 registers are reserved for the maker of the I/O card to be used for any

operations that are defined by and specific to any vendor unique operation.

Information about the use of these optional registers needs to be obtained from the

SDIO card maker. Reading and/or writing these registers without understanding the

vendor’s definitions may cause unexpected behavior or even damage to the card.

RFU

R/O

R/W

Reserved

for Vendors

Table 6-2 CCCR bit Definitions

SDIO Simplified Specification Version 2.00

6.10 Function Basic Registers (FBR)

In addition to the CCCR, each supported I/O function has a 256-byte area used to allow the host to quickly

determine the abilities and requirements of each function, enable power selection for each function and to

enable software loading. The address of this area is from 0x00n00 to 0x00nFF where n is the function number

(0x1 to 0x7). This per-function area is structured as follows:

Address

0x100

Function 1

CSA

enable

Function 1

supports

CSA

RFU

Function 1 Standard SDIO Function

interface code

0x101

0x102

Function 1 Extended standard SDIO Function interface code

RFU RFU RFU RFU RFU

RFU

EPS

SPS

0x103-0x108 Reserved for Future Use (RFU)

0x109-0x10B Pointer to Function 1 Card Information Structure (CIS)

0x10C-0x10E Pointer to Function 1 Code Storage Area (CSA)

0x10F

0x110-0x111

Data access window to Function 1 Code Storage Area (CSA)

I/O block size for Function 1

0x112-0x1FF Reserved for Future Use

0x200-0x7FF Function 2 to 7 Function Basic Information Registers (FBR)

0x800-0xFFF Reserved for Future Use

Table 6-3 Function Basic Information Registers (FBR)

The Individual bits and fields in the FBA are defined below in Table 6-4.

Field

SDIO

Standard

Function

interface

code

Type

R/O

Description

The SDIO Standard Function code identifies those I/O functions, which implement the

recommended standard interface as defined in a separate Application Specification. A

complete and current list of assigned standard codes shall be maintained and published

in any addendums to this specification. The codes assigned to those standard interfaces

at the time this specification was published are:

0x0 No SDIO standard interface supported by this function

0x1 This function supports the SDIO Standard UART

0x2 This function supports the SDIO Type-A for Bluetooth standard interface

0x3 This function supports the SDIO Type-B for Bluetooth standard interface

0x4 This function supports the SDIO GPS standard interface

0x5 This function supports the SDIO Camera standard interface

0x6 This function supports the SDIO PHS standard interface

0x7 This function supports the SDIO WLAN interface

0x8 This function supports the Embedded SDIO-ATA standard interface

(Embedded SDIO-ATA shall be implemented only on devices following the

“Embedded SDIO Specification”).

0x9-0x0E Not assigned, reserved for future use

0xF This function supports an SDIO standard interface number greater than 0xE. In this

case, the value in byte 0x101 identifies the standard SDIO interfaces type.

If this function supports and contains a Code Storage Area (CSA), this bit shall be set to 1.

If this function does not support a CSA, this bit shall be cleared to 0. CSA enable is

controlled by bit 7 of register 0xn00.

Function

Supports

CSA

R/O

SDIO Simplified Specification Version 2.00

Field

Function

CSA

Type

R/W

Description

This bit controls access to the Code Storage Area for this function. If this bit is cleared to

0, then any read or write access to the CSA shall be blocked. If this bit is set to 1, then

access to the CSA is allowed. This bit is cleared to 0 upon reset. If this function does not

support CSA (0xn00 bit 6=0), then this bit shall be R/O and always read as 0.

This is the extension of the SDIO Standard Function interface code. If the SDIO Standard

Function interface code is greater than 0xE, then this byte shall contain the code and the

standard code (0x100 bits 3-0) shall contain a value of 0xF. If the standard code is less

than 0xF, then this byte shall be 0x00.

Enable

Extended

SDIO

Standard

Function

interface

code

R/O

SPS

(Support

Power

Selection)

EPS

R/O

R/W

This bit indicates if the function has Power Selection.

SPS=0 :This function has no Power Selection. EPS shall be zero.

SPS=1 :This function has 2 power modes which are selected by EPS.

EPS=0(default): The function operates in Higher Current Mode

(Enable

Power

The maximum current for the function shall be given in TPLFE_HP_MAX_PWR_3.3V

EPS=1: The function works in Lower Current Mode

Selection)

The maximum current for the function shall be given in TPLFE_LP_MAX_PWR_3.3V

This bit shall be reset when IOEx=0.

Address

pointer to

Function

CIS

R/O

R/W

These three bytes make up a 24-bit pointer (only the lower 17 bits are used) to the start of

the Card Information Structure (CIS) that is associated with each function. The CIS is

defined in section 6.11. A CIS is mandatory for each function on an SDIO card. This

pointer is stored in little-endian format (LSB first). This register points to the End of Chain

tuple if the function is not supported on the card.

These three bytes make up a 24-bit pointer to the desired byte in the CSA to read or write.

After any read or write to the CSA access window register, this pointer shall be

automatically incremented by 1. If this function does not support CSA (0xn00 bit 6=0),

then these 24 bits shall be R/O and always read as 0x000000. This pointer is stored in

little-endian format (LSB first).

Address

pointer to

Function

CSA

Data

access

window to

CSA

Function

1-7 I/O

Block Size

R/W

Any read or write to this address when the CSA is enabled (0xn00 bit 7=1), shall pass

data to/from the byte addressed by the CSA address pointer. If this function does not

support CSA (0xn00 bit 6=0), then these 8 bits shall be R/O and always read as 0x00.

This 16-bit register sets the block size for I/O block operations for each function (1-7). If

this card does not support I/O block operations (SMB=0), then this register becomes

read-only and shall always read 0x0000. The maximum block size is 2048 (0x0800) and

the minimum is 1 (0x0001). At power-up or reset, this register shall be initially loaded with

a value of 0x0000. The host is responsible for setting the appropriate value for the block

size supported by each function. This pointer is stored in little-endian format (LSB first).

Table 6-4 FBR bit and field definitions

SDIO Simplified Specification Version 2.00

6.11 Card Information Structure (CIS)

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.

Address

0x0001000

- 0x017FFF

0x018000-

0x01FFFF

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

Reserved for Future Use

Table 6-5 Card Information Structure (CIS) and reserved area of CIA

The valid tuples (storage structures) from the PCMCIA specification and new tuples created for SDIO are

defined in section 16.7.

6.12 Multiple Function SDIO Cards

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.

6.13 Setting Block Size with CMD53

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)

SDIO Simplified Specification Version 2.00

6.14 Bus State Diagram

Figure 6-2 shows the Bus State Diagram for an SDIO card. It shows the bus states and their relations to SDIO

commands and Suspend/Resume.

Commands

accepted in “INI”

CMD5, CMD3

CMD15

Initialization

State

Power On

CMD3

CMD52 Reset

Commands

accepted in “TRN”

CMD52

Transfer

State

(Dat Bus Active)

BS=1

Standby

State

CMD53 (to valid

function)

Function

Resume

CMD7 with

incorrect RCA

Commands

accepted in “STB”

CMD3, CMD7,

CMD15

Execution complete

Function Suspend

CMD52 Abort

CMD7 with

correct RCA

Command

State

(Dat Bus Free)

BS=0

CMD15 or OCR

mismatch

Inactive

State

Commands

CMD7 with correct

accepted in “CMD”

CMD7, CMD52,

CMD53, CMD15

RCA

CMD53 to invalid

function

CMD53 to invalid function can be:

I/O Disable or I/O Not Ready (IORDY=0)

I/O Function number error in response

I/O Function already Suspended

Figure 6-2 State Diagram for Bus State Machine

SDIO Simplified Specification Version 2.00

7. Embedded I/O Code Storage Area (CSA)

In order to support the concept of “Plug-and-Play” for SDIO cards, each function contained in a card may need

to contain a block of memory for the storage of drivers and/or applications. In addition, since the same SDIO

card may be used on multiple different host platforms, several different versions of the code may be needed for

each function. One option is to store these programs in a standard SD Memory section of a combo card.

Alternately, a standard access means to load the code is contained in the optional Code Storage Area (CSA).

The CSA is a separate 16MB memory area that is accessed using the CSA address pointer and the CSA

window register contained in the FBR registers. Note that each function may have it’s own CSA to support it. The

CSA data can be read only or R/W. The actual storage method for the CSA is not a part of this specification and

left to the implementers.

7.1

CSA Access

In order for the host to access a function’s CSA, it first shall determine if that function supports a CSA. The host

reads the FBR register at address 0x00n00 where n is the function number (0x1 to 0x7). If bit 6=1, then the

function supports a CSA and the host enables access by writing bit 7=1. The next step is for the host to load the

24 bit address to start reading or writing. This is accomplished by writing the 24 bits (A23-0) to registers

0x00n0C to 0x00n0E where n is the function number (0x1 to 0x7). Once the start address is written, data can be

read or written by accessing register 0x00n0F, the CSA data window register. If more than 1 byte needs to be

read or written, an extended I/O command (byte or block) can be performed with an OP code of 0 (fixed

address). The address pointer shall be automatically incremented with each access to the window register, so

the access will be to sequential addresses within the CSA. Once the operation is complete, the address of the

NEXT operation shall be held in the 24 bit address register for the host to read.

7.2

CSA Data Format

The data stored in the CSA shall be structured using the FAT12/FAT16 format. This format is defined in the ISO

specification: ISO/IEC9293:1994 Information technology - Volume and file structure of disk cartridges for

information interchange. This specification is also the basis for the SD memory cards. The information on the

SD memory implementation can be found in the SDA publication: Part 2 FILE SYSTEM SPECIFICATION

Version 2.00 May 9, 2006. The actual layout of files within the CSA is undefined by this specification.

The use of the CSA for program or data storage for different host types requires that the SDIO card

manufacturer load the programs and data in a file format that may be recognized by the host. An example of this

would be the use of a specific file name saved within a specific subdirectory that is recognized and executed by

a particular host operating system. Such formats are specific and sometimes proprietary to different host

implementations and operating systems.

The rest of this chapter is not included in the Simplified Specification.

SDIO Simplified Specification Version 2.00

8. SDIO Interrupts

In order to allow the SDIO card to interrupt the host, an interrupt function is added to a pin on the SD interface.

Pin number 8, which is used as DAT[1] when operating in the 4-bit SD mode, is used to signal the card’s

interrupt to the host. The use of interrupt is optional for each card or function within a card. The SDIO interrupt is

“level sensitive”, that is, the interrupt line shall be held active (low) until it is either recognized and acted upon by

the host or de-asserted due to the end of the Interrupt Period (see 8.1.2). Once the host has serviced the

interrupt, it is cleared via some function unique I/O operation. All hosts shall provide pull-up resistors on all data

lines DAT[3:0] as described in section 6 of the SD Physical Specification.

8.1

Interrupt Timing

The operation of the interrupt pin is different between the SPI mode and the SD mode. The operation of the

interrupt pin is defined as follows:

8.1.1

SPI and SD 1-bit Mode Interrupts

In the SPI and 1-bit SD mode, Pin 8 is dedicated to the interrupt function. Thus, in the SPI and SD 1-bit modes

there are no timing constraints on interrupts. A card in the SPI or 1-bit SD mode signals an interrupt to the host

at any time by asserting pin 8 low. The host detects this pending interrupt using a level sensitive input. The host

is responsible for clearing the interrupt. If the SDIO card is operating in the SPI mode, the interrupt from the card

may not be asserted if the card is not selected.(CS=0). The exception to this requirement occurs only if the card

is both capable of interrupting when not selected (the SCSI bit in the CCCR = 1), and has that feature turned on

(the ECSI bit = 1). In this case, the card may assert the interrupt irrespective of the state of the CS line. For more

information, see Table 6-1.

8.1.2

SD 4-bit Mode

Since Pin 8 is shared between the IRQ and DAT[1] use in the 4-bit SD mode, an interrupt shall only be sent by

the card and recognized by the host during a specific time. The time that a low on Pin 8 shall be recognized as

an interrupt is defined as the Interrupt Period.

An SDIO host shall only sample the level on Pin 8 (DAT[1]/IRQ) into the interrupt detector during the Interrupt

Period. At all other times, the host interrupt controller shall ignore the level on Pin 8. Note that the Interrupt

Period is applicable for both memory and I/O operations

The definition of the Interrupt Period is different for operations with single block and multiple block data transfer.

8.1.3

Interrupt Period Definition

This section is not included in the Simplified Specification.

8.1.4

Interrupt Period at the Data Block Gap in 4-bit SD Mode (Optional)

This section is not included in the Simplified Specification.

8.1.5

Inhibited Interrupts (Removed Section)

This section is not included in the Simplified Specification.

8.1.6

End of Interrupt Cycles

This section is not included in the Simplified Specification.

SDIO Simplified Specification Version 2.00

8.1.7

Terminated Data Transfer Interrupt Cycle

This section is not included in the Simplified Specification.

8.1.8

Interrupt Clear Timing

Since the SDIO card uses level sensitive interrupts, the host shall clear pending interrupts with an I/O read or

write to some function unique area. In some host implementations, the sending of a CMD52 to the card is

handled by host adapter hardware while the host CPU can execute other operations. This condition may allow

an interrupt that has already been handled to re-interrupt the host if the timing of the interrupt clear is not

controlled. To prevent this condition, Any SDIO card that implements interrupts shall follow some required timing

with respect to removing the interrupt from the DAT[1] line after the write to the function unique area that clears

the interrupt. The clearing of the interrupt can be caused by an I/O write in a function unique method, or by a

function unique I/O read. An example of clearing an interrupt using an I/O read would be a function where the

reading of a data register may automatically clear the data ready interrupt.

The rest of this section is not included in the Simplified Specification.

SDIO Simplified Specification Version 2.00

9. SDIO Suspend/Resume Operation

The procedure used to perform the Suspend/Resume operation on the SD bus is:

1. The host determines which function is currently using the DAT[3:0] line(s).

2. The host requests the lower priority or slower transaction to suspend.

3. The host checks for the transaction suspension to complete.

4. The host begins the higher priority transaction.

5. The host waits for the completion of the higher priority transaction.

6. The host restores the suspended transaction.

If the current transaction can accept suspend and the card receives a suspend command during Read Wait, it

shall accept the suspend request.

The rest of this chapter is not included in the Simplified Specification.

SDIO Simplified Specification Version 2.00

10. SDIO Read Wait Operation

The optional Read Wait (RW) operation is defined only for the SD 1-bit and 4-bit modes. The read Wait

operation allows a host to signal a card that is executing a read multiple (CMD53) operation to temporarily stall

the data transfer while allowing the host to send commands to any function within the SDIO card. To determine

if a card supports the Read Wait protocol, the host shall test SRW capability bit in the Card Capability byte of the

CCCR (see Table 6-1). The timing for Read Wait is based on the Interrupt Period that is defined in section 8.1

If a card does not support the Read Wait protocol, the only means a host has to stall (not abort) data in the

middle of a read multiple command is to control the SDCLK. Read wait support is mandatory for the card to

support suspend/resume.

The rest of this chapter is not included in the Simplified Specification.

SDIO Simplified Specification Version 2.00

11. Power Control

11.1 Power Control Overview

The concept of high-power SDIO cards was introduced in Version 1.10 of the SDIO Specification. Power Control

supports following two features:

•

High-Power Support

SDIO cards created prior to Version 1.10 of the SDIO Specification were limited to a maximum current of

200mA at any time, irrespective of the number or types of functions supported. With the creation of wireless

communication devices in the SDIO form factor, a need was seen to provide more current to accommodate

the higher power requirements of some SDIO cards. Since backward compatibility is a primary concern for

any changes made to this specification, a method was chosen to prevent a high-power card from drawing

excessive amounts of current from hosts designed to only support the SDIO 1.0 cards. Master Power

Control allows standard and high-power cards to be inserted into any host without causing excessive

current damage to the host. It is important to note that there exists the possibility of trying to use a card that

requires high-power in a standard power host and having that card fail to operate. Master Power Control is

supported on a per card basis and available to the host in the CCCR. A high-power card may have a mix of

both high and standard power functions.

•

Power Selection Support

Not all hosts can supply enough current for all SDIO cards. A host may choose to use the SDIO card in a

lower power mode to increase operation time. Power Selection enables the host to switch the card to a

lower power mode. It is important to note that there exists the possibility of trying to use a standard power

card in a host that does not have enough power to meet the card’s requirement. In this case the card will fail

to operate. Cards supporting Power Selection will enable the widest range of host support. Power Selection

is supported on a per function basis and available to the host in the FBR.

11.2 Power Control support for SDIO Cards

11.2.1 Master Power Control

SDIO version 1.10 cards indicate their support for the new power control functions with the SMPC (Support

Master Power Control) bit in the CCCR (See section 6.9). Hosts enable the card’s power control functions with

the EMPC (Enable Master Power Control) bit.

SMPC can be set to 0 if the card maximum current is less than 200mA and Power Selection (see section 11.2.2)

is not supported. A SDIO version 1.10 card which has SMPC set to 1 shall maintain backward compatibility when

EMPC is set to 0. A SDIO version 1.0 host may not be aware of EMPC, which will remain 0 (its default state).

In the case where EMPC is set to 0, the card total current shall not exceed 200mA. Functions that exceed

200mA shall not set IORx to 1 and TPLFE_OP_MAX_PWR shall be set to 0. If a multi-function card’s total power

exceeds 200mA the card shall not set all IORx to 1, even if all IOEx are set to 1. Some of the functions’ IORx can

be set to 1 as long as the card’s total current is less than 200mA. If the host tries to enable a function (IOEx =1)

that will cause the card’s total current to exceed 200mA, the card shall disable (IORx=0) one or more functions

to keep the card’s total current less than 200mA. Which functions are enabled depends on the design of the card

vendor.

In the case where EMPC is set to 1, the card current can exceed 200mA, up to a maximum of 500mA. Card

should be designed, where possible, to not require the maximum current , thus functioning in as many hosts as

possible with sufficient power.

SDIO Simplified Specification Version 2.00

11.2.2 Power Selection

Power Selection defines two power modes for a function: Lower Current Mode and Higher Current Mode. A card

implementing Power Selection gives the host the choice between these two power modes. These modes can be

used for functions, such as a radio, which can operate in full performance (Higher Current Mode) or reduced

performance (Lower Current Mode). A card’s support of Power Selection is indicated with the SPS bit (Support

Power Selection) in the FBR. The host enables Power Selection with the EPS bit (Enable Power Selection) in

the FBR.

11.2.3 High-Power Tuples

Six new tuples are defined in version 1.10 for each function tuple.

•

Average power required when Master Power Control is not enabled (TPLFE_SP_AVG_PWR_3.3V)

Peak power required when Master Power Control is not enabled (TPLFE_SP_MAX_PWR_3.3V)

Average power required in Higher Current Mode (TPLFE_HP_AVG_PWR_3.3V)

Peak power required in Higher Current Mode (TPLFE_HP_MAX_PWR_3.3V)

Average power required in Lower Current Mode (TPLFE_LP_AVG_PWR_3.3V)

Peak power required in Lower Current Mode (TPLFE_LP_MAX_PWR_3.3V)

These values are 16 bits long with a 1mA/step resolution. This allows a value of 0 to 65,535 mA to be used.

Current varies depending on the voltage. These tuples are defined in 3.1-3.5V or 2.7-3.6V range. When a new

voltage range is added in future specification, another six tuples will be added.

Table 11-1 shows which tuples a host shall refer to depending on the host version and the settings of EMPC and

EPS bits.

Host

EMPC

EPS

Reference TPLs

Comments

Ver 1.0 Don’t care Don’t care TPLFE_OP_MIN_PWR

TPLFE_OP_AVG_PWR

TPFLE_OP_MAX_PWR

Ver 1.1

Don’t care TPLFE_SP_AVG_PWR_3.3V Same as TPLFE_OP_AVG_PWR

TPLFE_SP_MAX_PWR_3.3V Same as TPFLE_OP_MAX_PWR

TPLFE_HP_AVG_PWR_3.3V Non zero value is required when

TPLFE_HP_MAX_PWR_3.3V SMPC=1

TPLFE_LP_AVG_PWR_3.3V Non zero value is required when

TPLFE_LP_MAX_PWR_3.3V SPS=1

Table 11-1 Reference Tuples by Master Power Control and Power Select

A version 1.10 SDIO card shall implement the six new tuples. A card which has SMPC set to 1, shall set a

non-zero value to TPLFE_HP_AVG_PWR_3.3V and TPLFE_HP_MAX_PWR_3.3V. A card which has SPS set

to 1, shall set a non-zero value to TPLFE_LP_AVG_PWR_3.3V and TPLFE_LP_MAX_PWR_3.3V.

TPLFE_SP_AVG_PWR_3.3V and TPLFE_SP_MAX_PWR_3.3V should be set to the same value as

TPFLE_OP_AVG_PWR and TPLFE_OP_MAX_PWR respectively.

11.3 Power Control Support for the SDIO Host

11.3.1 Version 1.10 Host

The following are requirements for a version 1.10 host:

•

The host shall recognize new Power Control registers and tuples as defined in SDIO Specification

Version 1.10.

•

Power Control bits (SMPC, EMPC) in the CCCR

Power Selection bits (SPS, EPS) in the FBR

High-Power Tuples

•

The host shall know its own power supply ability

SDIO Simplified Specification Version 2.00

•

The host shall have the ability to manage power by calculating maximum current shown in the tuples

and control EMPC, EPS and IOEx not to exceed total current that the host can supply. If the host does

not have enough power to use the card, the host shall not enable the card.

11.3.2 Power Control Operation

A host reads the SMPC to see if the card supports Power Control additions. If so, the host checks SPS to see the

card’s support of Power Selection. If SMPC is set to 1, a version 1.10 host should set EMPC to 1.

Power Selection provides the host with the choice of two power modes for the function. A host that can supply

enough power to the card does not need to use Power Selection.

If SMPC is set to 1 and SPS is set to 1, the host can utilize Power Selection by setting EMPC to 1. If EPS is set

to 0 (default mode of the card), Higher Current Mode is selected. If EPS is set to 1, Lower Current Mode is

selected. For example, a wireless function may offer a power mode with reduced transmission range and

corresponding reduced current requirements. As the host knows how much current it can supply to the card, it

reads the appropriate tuples and decides whether or not to enable each function (with IOEX), and if so in what

Current Mode. The host shall verify that the total current required by the card shall not exceed the current of host

can supply. A version 1.10 host should read new tuples as shown in Table 11-1.

SDIO Simplified Specification Version 2.00

12. High-Speed Mode

High-Speed mode increases the bus clock rate to 50MHz and the SD bus throughput from 12.5MB/sec to

25MB/sec. For information on High-Speed mode for SD memory cards see Part 1 Physical Layer Specification

Version 2.00, sections 4.3.10, 4.3.11 and 6.8. SDIO and combo cards may also support High-Speed mode.

12.1 SDIO High-Speed Mode

SDIO version 1.20 cards indicate their support for High-Speed mode with the SHS (Support High-Speed) bit in

the CCCR (See section 6.9). Hosts switch between default and High-Speed mode with the EHS (Enable

High-Speed) bit in the CCCR by CMD52. Following a command to set or clear EHS, cards shall switch speed

mode within 8 clocks after the end bit of the corresponding response.

When switching from default to High-Speed mode the host can try to set EHS without first checking SHS. The

host issues CMD52 in RAW mode, setting EHS to one, and after getting the response of CMD52 the host

checks SHS and EHS. If SHS=0 or EHS=0, the command will be ignored and the card is still in default mode. If

SHS=1 and EHS=1, the card is in High-Speed Mode.

12.2 Switching Bus Speed Mode in a Combo Card

A combo card that supports High-Speed shall support it for both memory and IO. Two bus speed switch

commands are defined; SD memory command (CMD6) and SDIO command (EHS in CCCR is changed using

CMD52).

A part of this section is not included in the Simplified Specification.

When one bus speed switch commands is executed successfully, the card switches the card bus speed mode.

If two bus speed switch commands are executed in turn (to the same bus speed mode), only the first successful

command is effective to switch bus speed mode.

The host needs to check success of executing bus speed switch command and then the host can switch the

host bus speed mode to the same one.

Success of switching bus speed mode is determined by checking receipt of a good response and the result of

switching bus speed mode is the same as the switch requested.

The status of current bus speed mode is read by bus speed switch commands. For example, when bus speed

mode is switched by CMD6, the result can be read from EHS. If switching by RAW mode of CMD52 has failed,

there are two kinds of responses. One is no response with illegal command error. The other is that CMD52 is

accepted and the status of RAW mode indicates EHS is not changed.

A reset of either the memory or IO portion of a combo card will also reset both portions to default speed mode.

Within 8 clocks after response of a reset by CMD52 (write to RES in CCCR) or CMD0 the card shall change the

speed mode to default speed mode.

Note that when changing the bus speed the host bus driver should treat a bus speed change request from any

driver as an atomic operation. The host should mask interrupts and not issue any command to the card until the

bus speed change is complete.

If a combo card supports the Lock/unlock function, a locked card cannot change bus speed mode. A locked card

indicates an illegal command error to a bus speed switch command. The host needs to unlock the card by

CMD42 before changing bus speed. It also implies that a host should not change bus speed mode during

initialization before managing a locked card.

SDIO Simplified Specification Version 2.00

13. SDIO Physical Properties

This chapter is not included in the Simplified Specification.

13.1 SDIO Form Factors

The SDIO definition encompasses different form factors:

•

Full-Size SDIO — compatible with host sockets designed for SD memory cards

miniSDIO — compatible with host sockets designed for miniSD memory cards

13.2 Full-Size SDIO

The SDIO card is compatible with host sockets designed for SD memory cards. In addition, the SDIO cards can

be extended to allow for external connectors, antennas etc. With the exception of the write protect switch, all

SDIO cards shall meet the mechanical specifications described in the SD Physical Specification for that portion

of the card that is not extended. The WP switch is not supported by hosts for SDIO only cards.

The rest of this section is not included in the Simplified Specification.

13.3 miniSDIO

The miniSDIO card is compatible with host sockets designed for miniSD memory cards. In addition, the

miniSDIO cards can be extended to allow for external connectors, antennas etc. All miniSDIO cards shall meet

the mechanical specifications described in miniSD Card Addendum Version 2.00, Part 1 Physical Layer

Specification Version 2.00 for that portion of the card that is not extended.

When a miniSDIO card is inserted into a miniSD to SD memory card adaptor, and plugged-into an SDIO host

slot, it shall appear to the host as an SDIO card.

The rest of this section is not included in the Simplified Specification.

14. SDIO Power

14.1 SDIO Card Initialization Voltages

SDIO Version 2.00 eliminate the voltage range 2.0-2.7V for basic communication because the SD Physical

Specification Version 2.00 eliminates it. SDIO cards follow the same voltage and current requirements as SD

memory cards. This means that an SDIO or combo card shall be used at an operating voltage range of 2.7 to

3.6V. The hosts shall not supply the voltage range 2.0-2.7V for basic communication to the SDIO Version 2.00

cards.

14.2 SDIO Power Consumption

The SDIO cards are intended to operate in mobile devices that have limited power sources available. Because

the host’s battery life may be significantly reduced if the SDIO card draws excessive power, a primary goal of

SDIO designers should be low power. By reducing power consumption to a minimum, Host battery life and

consumer satisfaction will be enhanced. The following power data represents the maximum that a SDIO card

may draw. It is important for designers to note that a low power host may reject any SDIO card that identifies

SDIO Simplified Specification Version 2.00

itself as drawing more power that the host is willing to supply, thus lower power cards may have a competitive

advantage in the market.

The rest of this chapter is not included in the Simplified Specification.

SDIO Simplified Specification Version 2.00

15. Inrush Current Limiting

This chapter is not included in the Simplified Specification.

SDIO Simplified Specification Version 2.00

16. CIS Formats

16.1 CIS Reference Document

The CIS used by SDIO is based directly upon the metaformat specification used by PCMCIA and Compact

Flash. The user of this specification is directed to:

PC Card Standard

Volume 4

Metaformat Specification

Published by:

PCMCIA (Personal Computer Memory Card International Association)

2635 North First Street, Suite 209

San Jose, CA 95134 USA

+1-408-433-2273

+1-408-433-9558 (Fax)

16.2 Basic Tuple Format and Tuple Chain Structure

The Card Information Structure is one or more chains (or linked lists) of data blocks or tuples. The basic format

of tuples is shown in Table 16-1.

Byte

0x00

0x01

0x02..

(n+2)

TPL_CODE Tuple code: CISTPL_xxx

TPL_LINK Offset to next tuple in chain. This is the number of bytes in the tuple body. (n)

The tuple body. (n bytes)

Table 16-1 Basic Tuple Format

Byte 0 of each tuple contains a tuple code. A tuple code of 0xFF is a special mark indicating that there are no

more tuples in the chain. There are 2 tuples with only a tuple code, the CISTPL_NULL and the CISTPL_END

(see Table 16-2). These tuples do not have any additional bytes. For all other tuples, byte 1 of each tuple

contains a link to the next tuple in the chain. If the link field is 0, then the tuple body is empty. If the link field

contains 0xFF, then this tuple is the last tuple in its chain. There are two ways of marking the end of a tuple chain

for SDIO cards: a tuple code of 0xFF, or a tuple link of 0xFF. The use of an FFH link value is allowed in SDIO

cards, but it is recommended to use the End of Chain tuple. System software shall use the link field to validate

tuples. No SDIO card tuple can be longer than 257 bytes: 1 byte TPL_CODE + 1 byte TPL_LINK + FFH byte

tuple body (and this 257 byte tuple ends the chain). Some tuples provide a termination or stop byte that marks

the end of the tuple. In this case, the tuple can effectively be shorter than the value implied by its link field.

However, software shall not scan beyond the implied length of the tuple, even if a termination byte has not been

seen.

16.3 Byte Order Within Tuples

Within tuples, all multi-byte numeric data shall be recorded in little-endian order. That is, the least-significant

byte of a data item shall be stored in the first byte of a given field. Within tuples, all character data shall be stored

in the natural order. That is, the first character of the field shall be stored in the first byte of the field. Fixed-length

character fields shall be padded with null characters, if necessary.

SDIO Simplified Specification Version 2.00

16.4 Tuple Version

With the introduction of SDIO Specification Version 1.10, a different format for the tuple information is possible

based on the changes made by each specification revision. These changes could be added fields in a tuple or

entirely new tuples. In order to maintain backward compatibility, new data fields are added after existing fields in

order to maximize backward compatibility. It is the responsibility of the host program that is scanning the tuple

chain (sometimes called “walking the tuples”) to first determine the SDIO specification version that the card was

designed to. The program shall be designed to anticipate that SDIO cards will be encountered that are built to a

later version of the specification. This requires the program to ignore the additional data existing in SDIO cards

built to a later specification. Specifically, the program shall first read the SDIO specification version that the card

was designed to meet from the SDIOx field in the CCCR area. If the version is less than or equal to the version

of the tuple scan program, then the program shall know and properly decode all tuple information. If the card

version is greater than the scan program’s version, the scan program may need to ignore additional information

fields or tuples. The unknown tuples can be ignored by simply skipping those tuples with unrecognized codes.

Skipping is accomplished by using the TPL_LINK field (always the second byte) to jump over the unknown tuple.

In a similar manner, the additional data fields in tuples should be ignored using the link field. For example, if a

scan program is expecting 0x15 bytes of data and the TPL_LINK field indicates a size of 0x19 bytes, the scan

program should ignore and skip over the last 4 bytes of data.

16.5 SDIO Card Metaformat

Unlike the PCMCIA card, the SDIO card has multiple CIS areas. There is a common CIS for the entire card and

a CIS assigned to each function. Because of the multiple CIS areas, the SDIO card does not need to support the

CISTPL_LONGLINK_MFC tuple or the CISTPL_LINKTARGET as described in section 2.3.6 of the PCMCIA

spec. Table 16-2 lists the tuple codes supported by SDIO cards. The type field indicates if a tuple is Optional (O),

Mandatory (M), Recommended (R), or not applicable (n/a) for the common (function 0) tuple and for each

function (1-7) supported by the card. For more details on each tuple, see the PCMCIA metaformat specification

section referenced.

Code

Name

Description

PCMCIA

Type

Type Function

Reference Common

0x00

0x10

0x15

CISTPL_NULL

CISTPL_CHECKSUM Checksum control

CISTPL_VERS_1

CISTPL_ALTSTR

CISTPL_MANFID

Null tuple

3.1.9

3.1.1

3.2.10

Level 1

version/product-information

The Alternate Language String 3.2.1

Tuple

Manufacturer Identification

String Tuple

0x16

0x20

3.2.9

0x21

0x22

0x80-

0x8F

0x91

CISTPL_FUNCID

CISTPL_FUNCE

Function Identification Tuple

Function Extensions

Vendor Unique Tuples

3.2.7

3.2.6

None

n/a

CISTPL_SDIO_STD

Additional information for

functions built to support

application specifications for

standard SDIO functions.

Reserved for future use with 6.1.3

SDIO devices.

6.1.2

n/a

M¹:Standard

SDIO Function

O¹:non-Standard

SDIO Function

n/a

0x92

0xFF

CISTPL_SDIO_EXT

CISTPL_END

n/a

The End-of-chain Tuple

3.1.2

Table 16-2 Tuples Supported by SDIO Cards

SDIO Simplified Specification Version 2.00

Note 1: the use of CISTPL_SDIO_STD is mandatory for all functions that claim to support a SDIO standard

interface specification (see 1.3). If the function does not support a standard SDIO interface, this tuple should be

used with a value of 0.

16.6 CISTPL_MANFID: Manufacturer Identification String Tuple

The manufacturer identification tuple contains information about the manufacturer of a SDIO Card. Two types of

information are provided: the SDIO Card's manufacturer and a manufacturer card number. This tuple shall be

present in the card common CIS.

This should also be present in each function’s CIS. This allows a function to override the card common

manufacturer information so the driver can take advantage of unique features.

Byte

0x00

0x01

TPL_CODE CISTPL_MANFID (20H)

TPL_LINK Link to next tuple (at least 4)

TPLMID_MANF SDIO Card manufacturer code

0x02-0x03

0x04-0x05

TPLMID_CARD manufacturer information (Part Number and/or Revision)

Table 16-3 CISTPL_MANFID: Manufacturer Identification Tuple

The TPLMID_MANF field identifies the SDIO Card's manufacturer. New codes are assigned by both PCMCIA

and JEIDA. The first 256 identifiers (0x0000 through 0x00FF) are reserved for manufacturers who have JEDEC

IDs assigned by JEDEC Publication 106. Manufacturers with JEDEC IDs may use their eight-bit JEDEC

manufacturer code as the least significant eight bits of their SDIO Card manufacturer code. In this case, the

most significant eight bits shall be zero (0). For example, if a JEDEC manufacturer code is 89H, their SDIO Card

manufacturer code is 0x0089. If a SDIO card manufacturer does not currently have a TPLMID_MANF assigned,

one can be obtained at little or no cost from the PCMCIA. The TPLMID_CARD field is reserved for the use of the

SDIO Card's manufacturer. It is anticipated that the field will be used to store card identifier and revision

information.

16.7 SDIO Specific Extensions

SDIO cards use two to four tuples to provide additional information about the card (common) and each function.

The first is the Function ID tuple. The changes for SDIO are detailed in the next sections.

16.7.1 CISTPL_FUNCID: Function Identification Tuple

To identify an SDIO card, the CISTPL_FUNCID tuple shall exist in all CIS areas. This means there shall be a

CISTPL_FUNCID in the common CIS space chain and one in each function’s CIS space chain. The format of

this tuple is shown in

Byte

0x00

0x01

0x02

0x03

TPL_CODE CISTPL_FUNCID (0x21)

TPL_LINK Link to next tuple (0x02)

TPLFID_FUNCTION Card function code (0x0C)

TPLFID_SYSINIT System initialization bit mask. (Not used, set to 0x00)

Table 16-4 CISTPL_FUNCID Tuple

The function identification tuple contains information about the functionality provided by an SDIO Card.

Information is also provided to enable system utilities to decide if the SDIO Card should be configured during

system initialization. Since additional function specific information is available, one or more function extension

tuples follow this tuple. The TPLFID_FUNCTION field contains an identifier assigned by PCMCIA (0x0C) to

identify the SDIO device class.

SDIO Simplified Specification Version 2.00

16.7.2 CISTPL_FUNCE: Function Extension Tuple

The CISTPL_FUNCE tuple provides standard information about the card (common) and each individual

function. There shall be one CISTPL_FUNCE in each function’s CIS immediately following the

CISTPL_FUNCID tuple. The format of the CISTPL_FUNCE is shown in Table 16-5.

Byte

0x00

TPL_CODE CISTPL_FUNCE (0x22)

0x01

TPL_LINK Link to next tuple (see following sections)

0x02

0x03-n

TPLFE_TYPE Type of extended data (see following sections)

TPLFE_DATA Function information (see following sections)

Table 16-5 CISTPL_FUNCE Tuple General Structure

There are two versions of the CISTPL_FUNCE tuple, one for the common CIS (function 0) and a version used

by the individual function’s CIS (1-7). Both types are described below.

16.7.3 CISTPL_FUNCE Tuple for Function 0 (common)

This version of the CISTPL_FUNCE tuple gives the host common information about the card. There shall be

only one of these tuples, located in the CIS for function 0 following the CISTPL_FUNCID. The format of this

tuple is shown in Table 16-6.

Byte

0x00

0x01

TPL_CODE CISTPL_FUNCE (0x22)

TPL_LINK Link to next tuple (0x04)

0x02

0x03-0x04

0x05

TPLFE_TYPE Type of extended data (0x00)

TPLFE_FN0_BLK_SIZE

TPLFE_MAX_TRAN_SPEED

Table 16-6 TPLFID_FUNCTION Tuple for Function 0 (common)

The fields in this tuple have the following definition:

Field

Description

TPLFE_FN0_BLK_SIZE

This is both the maximum block size and byte count that function 0 can

support. A value of zero is not valid and shall not be used.

TPLFE_MAX_TRAN_SPEED This byte indicates the maximum transfer rate per one data line during

data transfer. This value applies to all functions in the SDIO card. This

value shall be 25 Mb/Sec (0x32) for all Full-Speed SDIO cards. The

minimum value for Low-Speed SDIO cards shall be 400 Kb/Sec (0x48).

The format is identical to the TRAN_SPEED value stored in the CSD of

SD memory cards. The maximum data transfer rate is coded according

to the following method:

Bits 2:0 contain the transfer rate unit coded as follows:

0=100kbit/s, 1=1Mbit/s, 2=10Mbit/s, 3=100Mbit/s, 4... 7=reserved

Bits 6:3 contain the time value codes as follows:

0=reserved, 1=1.0, 2=1.2, 3=1.3, 4=1.5, 5=2.0, 6=2.5, 7=3.0, 8=3.5,

9=4.0, A=4.5, B=5.0, C=5.5, D=6.0, E=7.0, F=8.0

Bit 7 is reserved and shall be zero

A Combo Card shall support 25MHz clock (0x32)

Table 16-7 TPLFID_FUNCTION Field Descriptions for Function 0 (common)

SDIO Simplified Specification Version 2.00

16.7.4 CISTPL_FUNCE Tuple for Function 1-7

This version of the CISTPL_FUNCE tuple gives the host common information about each individual function on

a per-function basis. There shall be one of these tuples, located in the CIS for each function following the

CISTPL_FUNCID. The format of this tuple is shown in Table 16-8.

Byte

0x00

0x01

0x02

0x03

TPL_CODE CISTPL_FUNCE (0x22)

TPL_LINK Link to next tuple (0x2A)

TPLFE_TYPE Type of extended data (0x01)

TPLFE_FUNCTION_INFO

TPLFE_STD_IO_REV

0x04

0x05-0x08

0x09-0x0C

0x0D

0x0E-0x0F

0x10-0x13

0x14

TPLFE_CARD_PSN

TPLFE_CSA_SIZE

TPLFE_CSA_PROPERTY

TPLFE_MAX_BLK_SIZE

TPLFE_OCR

TPLFE_OP_MIN_PWR

0x15

TPLFE_OP_AVG_PWR

0x16

0x17

TPLFE_OP_MAX_PWR

TPLFE_SB_MIN_PWR

0x18

TPLFE_SB_AVG_PWR

0x19

TPLFE_SB_MAX_PWR

0x1A-0x1B

0x1C-0x1D

0x1E-0x1F

0x20-0x21

0x22-0x23

0x24-0x25

0x26-0x27

0x28-0x29

0x2A-0x2B

TPLFE_MIN_BW

TPLFE_OPT_BW

TPLFE_ENABLE_TIMEOUT_VAL

TPLFE_SP_AVG_PWR_3.3V

TPLFE_SP_MAX_PWR_3.3V

TPLFE_HP_AVG_PWR_3.3V

TPLFE_HP_MAX_PWR_3.3V

TPLFE_LP_AVG_PWR_3.3V

TPLFE_LP_MAX_PWR_3.3V

Table 16-8 TPLFID_FUNCTION Tuple for Function 1-7

The fields in this tuple have the following definition:

Field

Description

TPLFE_FUNCTION_INFO

Bit significant information about the Function The bits are defined in Table

16-10

TPLFE_STD_IO_REV

This 8-bit value contains the version level of the Application Specification

for Standard SDIO Functions that this function supports. The format is x.y

where x is the major version (4-bits) and y is the minor version level. For

example if the version is 2.4 the value would be 0x24. If this function does

not support an SDIO standard function, the value shall be 0x00.

The Product Serial Number is a 32 bit unsigned binary integer. Support of

a serial number is optional, if there is no serial number, this field shall be

0x00000000 While a unique serial number is not required for all devices,

it is strongly recommended that SDIO card vendors place a unique serial

number in this field to assist the operating systems is differentiating

multiple cards of the same type. Also note that some Application

Specifications for Standard SDIO Functions require a unique serial

number in this field. The individual Application Specification will indicate if

support of this field is mandatory.

TPLFE_CARD_PSN

SDIO Simplified Specification Version 2.00

TPLFE_CSA_SIZE

Size of the CSA space available for this function in bytes

TPLFE_CSA_PROPERTY

This byte contains flags identifying properties of this function’s CSA. The

bits are defined in Table 16-11

TPLFE_MAX_BLK_SIZE

TPLFE_OCR

This is both the maximum block size and byte count that this function can

support. A value of zero is not valid and shall not be used.

This is the OCR value for this function. The format is identical to the 32-bit

OCR format used by SD memory devices. For more details, see section

5.1 of the SD Physical Specification.

TPLFE_OP_MIN_PWR

TPLFE_OP_AVG_PWR

TPLFE_OP_MAX_PWR

TPLFE_SB_MIN_PWR

This is the minimum current, in mA, required by this function when

operating. This value is valid for all voltages supported by this function. If

the required current exceeds 200mA, this value shall be zero.

This is the average current, in mA, required by this function when

operating. This value is valid for all voltages supported by this function. If

the required current exceeds 200mA, this value shall be zero

This is the maximum (peak) current, in mA, required by this function when

operating. This value is valid for all voltages supported by this function. If

the required current exceeds 200mA, this value shall be zero

This is the minimum current, in mA, required by this function when in the

standby condition. If this function does not support standby, this value

shall be 0x00. The method to place this function in the standby state and

the capabilities it has while in standby are vendor defined. This value is

valid for all voltages supported by this function. Note that this value is

valid only for standard power SDIO cards or high-power cards when

EMPC is 0. With an 8-bit field, the range is from 0 to 254 mA. A value of

255 (0xFF) is used to indicate a value of 255mA or greater.

TPLFE_SB_AVG_PWR

TPLFE_SB_MAX_PWR

This is the average current, in mA, required by this function when in the

standby condition. If this function does not support standby, this value

shall be 0x00. The method to place this function in the standby state and

the capabilities it has while in standby are vendor defined. This value is

valid for all voltages supported by this function. Note that this value is

valid only for standard power SDIO devices cards or high-power cards

when EMPC is 0. With an 8-bit field, the range is from 0 to 254 mA. A

value of 255 (0xFF) is used to indicate a value of 255mA or greater.

This is the maximum current, in mA, required by this function when in the

standby condition. If this function does not support standby, this value

shall be 0x00. The method to place this function in the standby state and

the capabilities it has while in standby are vendor defined. This value is

valid for all voltages supported by this function. Note that this value is

valid only for standard power SDIO devices cards or high-power cards

when EMPC is 0. With an 8-bit field, the range is from 0 to 254 mA. A

value of 255 (0xFF) is used to indicate a value of 255mA or greater.

This is the minimum data transfer bandwidth, in KB/sec, needed by this

function to successfully operate. If this function has no minimum

necessary bandwidth, these bytes shall be 0x0000.

TPLFE_MIN_BW

TPLFE_OPT_BW

This is the data transfer bandwidth, in KB/sec, needed by this function to

function at an optimum level. If this function has no optimum bandwidth,

these bytes shall be 0x0000.

TPLFE_ENABLE

TIMEOUT_VAL

(Added in SDIO Rev 1.1) This 16-bit value indicates the function’s

required time-out value for coming ready after being enabled. This

per-function value indicates the time a host should wait from asserting

IOEx until expecting the card to indicate ready by asserting IORx.

Different SDIO functions take different amounts of time to become ready

after being enabled due to different internal initialization requirements.

The required time-out limit is in 10mS steps, allowing a range of 0-655.35

SDIO Simplified Specification Version 2.00

seconds. If the cards required no time-out, this field shall be set to

0x0000.

TPLFE_SP_AVG_PWR_3.3V

TPLFE_SP_MAX_PWR_3.3V

TPLFE_HP_AVG_PWR_3.3V

This value is the same as that of TPLFE_OP_AVG_PWR.

This value is the same as that of TPLFE_OP_MAX_PWR.

This 16-bit value indicates the average current, in mA, required by this

function when operating in the Higher Current Mode (EMPC=1 & EPS=0).

This value indicates a current range from 1 to 65535 mA.

This 16-bit value indicates the peak current, in mA, required by this

function when operating in the Higher Current Mode. This value indicates

a current range from 1 to 65535 mA.

This 16-bit value indicates the average current, in mA, required by this

function when operating in the Lower Current Mode (EMPC=1 & EPS=1).

This value indicates a current range from 1 to 65535 mA

This 16-bit value indicated the maximum (peak) current, in mA, required

by this function when operating in the Lower current mode (EMPC=1 &

EPS=1). This value indicates a current range from 1 to 65535 mA

TPLFE_HP_MAX_PWR_3.3V

TPLFE_LP_AVG_PWR_3.3V

TPLFE_LP_MAX_PWR_3.3V

Table 16-9 TPLFID_FUNCTION Field Descriptions for Functions 1-7

Bit

Name

RFU

FN_WUS

Table 16-10 TPLFE_FUNCTION_INFO Definition

The FN_WUS (Wake Up Support) bit signals the function’s support of wake-up when the function is placed into

a low power state and the SDCLK is stopped. The intent is to allow a SDIO card to be placed into a low power

condition and still signal the host of a wake-up event. If this bit is set to 1, then this function may be placed into

a low power state using some function standard or vendor defined method and the SDCLK can be stopped with

the power remaining applied to the card. Irrespective of the state of this bit, the host may stop the SDCLK as

allowed by the SD Physical Specification.

Bit

Name

RFU

CSA_NF CSA_WP

Table 16-11 TPLFE_CSA_PROPERTY Definition

The CSA_WP bit is used to write protect the CSA for this function, or identifies it as read-only. If this bit is set to

1, then the CSA of this function is either write protected or read-only. If this bit is clear, then the host may write

the CSA. Setting of this bit for R/W devices is handled in a vendor-defined method.

The CSA_NF bit is used to indicate to the host that the CSA area should not be reformatted. If the bit is set to 1,

the host may not format the CSA file structure. If this bit is cleared to 0, then the host may reformat the file

system of the CSA.

SDIO Simplified Specification Version 2.00

16.7.5 CISTPL_SDIO_STD: Function is a Standard SDIO Function

This tuple code (0x91) has been reserved for use by SDIO devices that conform to the application specifications

for standard SDIO functions, as defined in those separate specifications. The exact format for this tuple can be

found in those specifications. The basic format only is provided here and the reader is directed to the

appropriate Application Specification for Standard SDIO Functions for more complete details:

Byte

0x00

0x01

TPL_CODE CISTPL_SDIO_STD (91h)

TPL_LINK Link to next tuple (2 ≤ n ≤ 255)

n is the number of bytes in the tuple body

TPLSDIO_STD_ID

0x02

0x03

TPLSDIO_STD_TYPE

0x04 ... (n+1)

TPLSDIO_STD_DATA

If n = 2, TPLSDIO_STD_DATA does not exist.

Table 16-12 CISTPL_SDIO_STD: Tuple Reserved for SDIO Cards

The fields in this tuple have the following definition:

Field

Description

TPLSDIO_STD_ID

This 8-bit code identifies the Standard SDIO Function type for which this

tuple supplies additional information. The available codes can be found in

the I/O device interface code entry of the FBR (see 6.10)

This 8-bit value identifies the format and type of data contained within the

body of this tuple. If this value is 0x00, then only 1 standard data structure

has been defined for this Standard SDIO Function. If this value is

non-zero, then this byte identifies which tuple data format is being used for

the data. This code is defined in the Application Specification for Standard

SDIO Functions.

TPLSDIO_STD_TYPE

TPLSDIO_STD_DATA

The data component of this tuple (n-2 bytes). The format of this data

structure is defined in the Application Specification for Standard SDIO

Functions.

16.7.6 CISTPL_SDIO_EXT: Tuple Reserved for SDIO Cards

This tuple code (0x92) has been reserved for future use by SDIO cards. The actual format of the data has not

been established at this time. The basic format of this tuple is:

Byte

0x00

0x01

TPL_CODE CISTPL_SDIO_EXT (92h)

TPL_LINK Link to next tuple (0 ≤ n ≤ 255)

n is the number of bytes in the tuple body

0x02 ... (n+1)

TPLSDIO_EXT_DATA The data component of this tuple (n bytes)

If n=0, TPLSDIO_EXT_DATA does not exist.

Table 16-13 CISTPL_SDIO_EXT: Tuple Reserved for SDIO Cards

SDIO Simplified Specification Version 2.00

Appendix A

(Normative)

A.1 SD and SPI Command List

Table A-14 and Table A-15 show the commands that are supported by SD memory and SDIO devices in both

SPI and SD modes. If a command is not identified as either mandatory or optional, then it is not supported by

that device.

Supported

Commands

CMD0

SDMEM

System

Mandatory

Optional

SDIO

System

Mandatory

Abbreviation

Comments

GO_IDLE_STATE

Used to change from SD to SPI mode

CID not supported by SDIO

CMD2

ALL_SEND_CID

CMD3

SEND_RELATIVE_ADDR

SET_DSR

Mandatory

Mandatory¹Added in Part 1 v1.10

Mandatory

CMD4

DSR not supported by SDIO

CMD5

IO_SEND_OP_COND

SWITCH_FUNC

CMD6

Mandatory¹

Mandatory

Optional

CMD7

SELECT/DESELECT_CARD

SEND_CSD

CMD9

CSD not supported by SDIO

CID not supported by SDIO

CMD10

CMD12

CMD13

CMD15

CMD16

CMD17

CMD18

CMD24

CMD25

CMD27

CMD28

CMD29

CMD30

CMD32

CMD33

CMD38

CMD42

CMD52

CMD53

CMD55

CMD56

ACMD6

ACMD13

ACMD22

ACMD23

ACMD41

ACMD42

ACMD51

SEND_CID

STOP_TRANSMISSION

SEND_STATUS

Card Status includes only SDMEM information

GO_INACTIVE_STATE

SET_BLOCKLEN

READ_SINGLE_BLOCK

READ_MULTIPLE_BLOCK

WRITE_BLOCK

Mandatory

WRITE_MULTIPLE_BLOCK

PROGRAM_CSD

SET_WRITE_PROT

CLR_WRITE_PROT

SEND_WRITE_PROT

ERASE_WR_BLK_START

ERASE_WR_BLK_END

ERASE

CSD not supported by SDIO

Optional

Mandatory

Optional

LOCK_UNLOCK

IO_RW_DIRECT

Mandatory

IO_RW_EXTENDED

APP_CMD

Block mode is optional

Mandatory

GEN_CMD

SET_BUS_WIDTH

SD_STATUS

SEND_NUM_WR_BLOCKS

SET_WR_BLK_ERASE_COUNT Mandatory

SD_APP_OP_COND

SET_CLR_CARD_DETECT

SEND_SCR

Mandatory

SCR not supported by SDIO

Table A-14 SD Mode Command List

¹For Part 1 v1.10 or higher Memory or Combo Cards

SDIO Simplified Specification Version 2.00

Supported

Abbreviation

Commands

SDMEM

System

SDIO

System

Comments

CMD0

GO_IDLE_STATE

SEND_OP_COND

IO_SEND_OP_COND

SWITCH_FUNC

Mandatory

Used to change from SD to SPI mode

CMD1

CMD5

Mandatory

CMD6

Mandatory¹

Mandatory

Optional

Mandatory¹Added in Part 1 v1.10

CSD not supported by SDIO

CID not supported by SDIO

CMD9

SEND_CSD

CMD10

CMD12

CMD13

CMD16

CMD17

CMD18

CMD24

CMD25

CMD27

CMD28

CMD29

CMD30

CMD32

CMD33

CMD38

CMD42

CMD52

CMD53

CMD55

CMD56

CMD58

CMD59

ACMD13

ACMD22

ACMD23

ACMD41

ACMD42

ACMD51

SEND_CID

STOP_TRANSMISSION

SEND_STATUS

Card Status includes only SDMEM information.

SET_BLOCKLEN

READ_SINGLE_BLOCK

READ_MULTIPLE_BLOCK

WRITE_BLOCK

WRITE_MULTIPLE_BLOCK

PROGRAM_CSD

SET_WRITE_PROT

CLR_WRITE_PROT

SEND_WRITE_PROT

ERASE_WR_BLK_START

ERASE_WR_BLK_END

ERASE

CSD not supported by SDIO.

Optional

Mandatory

Optional

LOCK_UNLOCK

IO_RW_DIRECT

IO_RW_EXTENDED

APP_CMD

Mandatory

Block mode is optional

Mandatory

GEN_CMD

READ_OCR

CRC_ON_OFF

Mandatory

SD_STATUS

SEND_NUM_WR_BLOCKS

SET_WR_BLK_ERASE_COUNT Mandatory

SD_APP_OP_COND

SET_CLR_CARD_DETECT

SEND_SCR

Mandatory

SCR includes only SD-MEM information.

Table A-15 SPI Mode Command List

¹For Part 1 v1.10 or higher Memory or Combo Cards

SDIO Simplified Specification Version 2.00

Appendix B

(Normative)

B.1 Normative References

The following documents are referenced by this specification.

This specification can apply to any released versions of below SD Specifications after Version 2.00.

1) SD Specifications Part 1 PHYSICAL LAYER SPECIFICATION

Version 2.00 May 9, 2006

2) SD Specifications Part 1 miniSD Card Addendum

Version 2.00 January 30, 2007

3) SD Specifications Part 2 FILE SYSTEM SPECIFICATION

Version 2.00 May 9, 2006

4) ISO/IEC9293:1994

Information technology - Volume and file structure of disk cartridges for information interchange

5) PC CARD STANDARD Release 8.1 2002

Volume 4 Metaformat Specification

SDIO Simplified Specification Version 2.00

Appendix C

C.1 Abbreviations and Terms

The original 3 companies that established the SDA and the SD card

specification

ACMD

Application CommanD An additional set of commands created to support SD

specific requirements.

Block

CCCR

A number of bytes, basic data transfer unit

Common Card Control Registers

Connect/Disconnect

CIA

Common Information Area

CID

Card IDentification number register

Card Information Structure

Clock signal

CIS

CLK

CMD

Command line or SD bus command (if extended CMDXX)

A card that includes both SDIO and SD memory

Cyclic Redundancy Check

Combo Card

CRC

Chip or Card Select

CSA

Code Storage Area

CSD

Card Specific Data register

Data line where x is in the range of 0 to 3

Driver Stage Register

DAT[x]

DSR

ECC

Error Correction Code

Embedded SDIO

I/O or combo devices that are embedded in a host device that utilize the SDIO

electrical and command interface, but are not intended to be removed.

EMI

Electro-Magnetic Interference

External Signal Contacts

ESC

ESD

Electro-Static Discharge

FAT

File Allocation Table

FBR

Function Basic Registers

FIFO

First In-First Out buffer

Flash

A type of multiple time programmable non volatile memory

Full-Size SDIO Card

A SDIO card with physical dimensions based on SD Physical Specification

Version 1.01

Function

An I/O device contained within an SDIO card

High-Power SDIO

A SDIO device that requires up to 500 mA rather than the standard 200 mA

allowed for a Standard-Power SDIO device

hi-Z

A three-state driver in the high-impedance state

Interrupt

A signal from the SDIO device to the host signaling the need for attention

The times that a card may generate an interrupt signal on the SD bus

SD Slot that supports only the SD Physical Specification Version 1.01

Interrupt Period

Legacy Slot

SDIO Simplified Specification Version 2.00

LOW, HIGH

MBIO

Binary interface states with defined assignment to a voltage level

Multi-Block I/O

miniSDIO Card

MMC

A SDIO card based on the miniSD card form factor.

MultiMedia Card

MSB, LSB

OCR

The Most Significant Bit or Least Significant Bit

Operation Conditions Register

PCMCIA

PnP

Personal Computer Memory Card International Association

Plug and Play a means to identify an SDIO device and optionally load

applications and/or drivers without user intervention

R/O

Read Only

R/W

Read or Write

RAW

Read After Write

RCA

Relative Card Address register

Re-starting the temporarily halted data transfer

Reserved for Future Use. Normally Read-Only and set to 0

Read Only Memory

Resume

RFU

ROM

RWC

SCR

Read Wait Control

SD Configuration Register

SD Association

SDA

SDCLK

SDIO

SDIO aware

SPI

SD clock signal

SD Input/Output

A host designed to support the signals and protocol of SDIO devices

Serial Peripheral Interface

Standard-Power SDIO A SDIO device that operates with 200 mA or less of current at all times.

Stuff bit(s)

Filling bit(s) to ensure fixed length frames for commands and responses.

Suspend

Temporarily halting the transfer of data

To Be Determined (in the future)

TBD

Three-state driver

A driver stage which has three output driver states: HIGH, LOW and high

impedance (which means that the interface does not have any influence on the

interface level)

Tuple

VDD

VSS

W/O

Data blocks in a linked list or chain format

+ Power supply

Power supply ground

Write Only

Write Protect

SDIO Simplified Specification Version 2.00

Appendix D

(Informative)

Appendix D is not included in the Simplified Specification.

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