The CompactFlash Association was founded in 1995 by a group of international companies and today focuses on the common goal of creating industry standards for flash-based memory cards targeted at the professional imaging, video and industrial markets. The CompactFlash Association focuses on the development of specifications, conformance testing procedures and tools, and marketing activities to promote CFA products, technology and applications. Today, the CompactFlash Association has approximately 80 members involved in the design, development, manufacture or sale of products that use CFA specifications and technologies.
The CompactFlash interface is a 50-pin subset of the 68-pin PCMCIA connector. “It can be easily plugged into a passive 68-pin PCMCIA Type II to CF Type I adapter that fully complies with PCMCIA electrical and mechanical interface specifications,” according to compactflash.org. The interface operates as either a 16-bit PC Card (0x7FF address boundary) or an IDE (PATA) interface, depending on the state of a mode pin at power-up. The CompactFlash interface can be used as IDE (PATA) interface. In contrast to the PC card interface, the CompactFlash interface does not have special programming voltages (Vpp1 and Vpp2).
CompactFlash IDE mode defines an interface that is smaller than, but electrically identical to, the ATA interface. The CF device contains an ATA controller and appears to the host device like a hard disk. CF devices operate at 3.3 volts or 5 volts and can be interchanged from system to system. CompactFlash supports C-H-S and 28-bit logical block addressing (CF 5.0 introduced support for LBA-48). CF cards with flash memory are able to withstand extremely rapid temperature changes. Industrial versions of flash memory cards can operate in a range from -45 °C to +85 °C.