FAQ for Secure Digital I/O Device Support in Windows
Updated: October 28, 2010
This paper answers frequently asked questions about native support for Secure Digital I/O devices for the Microsoft Windows family of operating systems.
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Secure Digital (SD) is a standard for connecting flash memory and I/O devices to a host (such as a PC, PDA, phone, camera, or GPS). Secure Digital I/O (SDIO) devices such as memory cards are extremely small solid-state cards that provide high capacity non-volatile storage.
Q. How does Windows support Secure Digital card devices?
Microsoft has written a Secure Digital (SD) bus driver that follows the SDIO Standard Host Controller Specification 1.0. The SD bus driver was first released to system manufacturers in an out-of-band release in June 2003 and supports Memory, MMC, and SDIO media. The SD bus driver is included in Windows XP SP2 and later versions of Windows. Native support for SD storage devices is also included.
Q. How is SD licensed for use with Windows operating systems?
Hardware manufacturers must license SD through the SD Card Association. For information, visit the SD Card Association Web site. .
For information about licensing Microsoft SD drivers for redistribution, send email to email@example.com.
Q. What versions of Windows support SD?
SD is supported natively in Windows 7, Windows Vista, Microsoft Windows XP, and Windows CE 5.0.
SD support for Windows 2000 is available as an out-of-band release in the optional OPK update released in June 2003.
Q. What kinds of devices are supported by the SD bus driver?
The SD bus driver supports storage and I/O devices that are compatible with the SDIO specification. Drivers for SDIO storage devices are included in the release. Hardware manufacturers of I/O devices can use the exposed SDIO APIs to write drivers for their devices.
Q. How do I get my SD device to work with the SD bus driver?
For SDIO cards, you must build an SDIO function driver that is compatible with the Microsoft SD bus driver using the SD header and library included in the Windows Driver Kit (WDK). SD storage cards are already supported natively. SD host controllers are supported as long as they are a PCI-based SDA standard host controller that complies fully with SD Host Specification 1.0. Proprietary SD host controllers or controllers with proprietary extensions are not supported.
Q. How can I get the SD header and library so I can write a driver?
The SD header file and library are provided with the WDK and the Windows Server 2003 SP1 Driver Development Kit (DDK).
Q. Where can I find documentation about writing an SD device driver?
Related SD APIs and driver development documentation is available on MSDN in the Windows Driver Kit documentation under Buses > SD Bus.
Q. Where can I get more information?
If you have a question that is not answered in this FAQ or the SD documentation in the Windows DDK, send e-mail to firstname.lastname@example.org.
SD Card Association
Microsoft Windows Driver Kit (WDK)