This document explains how the operating system supports the card function extensions to SD technology.Ĭard readers for many early SD storage devices were designed to connect to the USB bus.
Secure Digital (SD) card technology began with portable, miniature memory cards, but with the release of the Secure Digital I/O (SDIO) specification, the Secure Digital Association (SDA) has broadened the definition of SD technology to include a large variety of card functions, such as Bluetooth devices, video cameras, Wireless LAN devices, and Global Positioning System (GPS) receivers.
