CompactFlash (CF) is a
flash memory
Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates. Both us ...
mass storage device
In computing, mass storage refers to the storage of large amounts of data in a persisting and machine-readable fashion. In general, the term is used as large in relation to contemporaneous hard disk drives, but it has been used large in relati ...
used mainly in portable electronic devices. The format was specified and the devices were first manufactured by
SanDisk
SanDisk is a brand for flash memory products, including memory cards and readers, USB flash drives, solid-state drives, and digital audio players, manufactured and marketed by Western Digital. The original company, SanDisk Corporation was acquir ...
in 1994.
CompactFlash became one of the most successful of the early memory card formats, surpassing
Miniature Card
The Miniature Card or MiniCard is a flash or SRAM memory card standard first promoted by Intel in 1995. The card was backed by Advanced Micro Devices, Fujitsu and Sharp Electronics. They are no longer manufactured. The Miniature Card Implementers ...
and
SmartMedia
SmartMedia is an obsolete flash memory card standard owned by Toshiba, with capacities ranging from 2 MB to 128 MB. The format mostly saw application in the early 2000s in digital cameras and audio production. SmartMedia memory cards a ...
. Subsequent formats, such as
MMC/
SD, various
Memory Stick
The Memory Stick is a removable flash memory card format, originally launched by Sony in late 1998. In addition to the original Memory Stick, this family includes the Memory Stick PRO, a revision that allows greater maximum storage capacity an ...
formats, and
xD-Picture Card
The xD-Picture Card is an obsolete form of flash memory card, used in digital cameras made by Olympus and Fujifilm during the 2000s. The xD in the xD-Picture Card stands for eXtreme Digital.
xD cards were manufactured with capacities of 16&nb ...
offered stiff competition. Most of these cards are smaller than CompactFlash while offering comparable capacity and speed. Proprietary memory card formats for use in professional audio and video, such as
P2 and
SxS
SxS (S-by-S) is a flash memory standard compliant to the Sony and SanDisk-created ExpressCard standard. According to Sandisk and Sony, the cards have transfer rates of 800 Mbit/s and burst transfer rate of up to 2.5 Gbit/s over the ExpressCard's ...
, are faster, but physically larger and more costly.
CompactFlash's popularity is declining as
CFexpress
CFexpress is a standard for removable media cards proposed by the CompactFlash Association (CFA). The standard uses PCIe 3.0 interface with 1 to 4 lanes where 1 GB/s data can be provided per lane. NVM Express is also supported to provide low overh ...
is taking over. As of 2022, both Canon and Nikon newest high end cameras, e.g. the
Canon EOS R5
The Canon EOS R5 is a full-frame mirrorless interchangeable-lens camera officially announced by Canon on July 9, 2020 alongside the lower-resolution EOS R6 and various new RF mount lenses. While it is not a direct successor to any of Canon's p ...
,
Canon EOS R3
The Canon EOS R3 is a 24 megapixel full-frame mirrorless interchangeable-lens camera launched by Canon officially announced by Canon on 14 September 2021 alongside two RF mount lenses. The camera is available as body only with a MSRP of US$5,999 ...
, and
Nikon Z 9
The Nikon Z 9 is a full-frame mirrorless camera produced by Nikon. The camera was announced on October 28, 2021.
The Z 9 has the same 45.7 MP resolution as the Z 7 and Z 7II cameras, but uses a much faster stacked CMOS sensor which improves a ...
use CFexpress cards for the higher performance required to record 8K video.
Traditional CompactFlash cards use the
Parallel ATA interface, but in 2008, a variant of CompactFlash,
CFast
CompactFlash (CF) is a flash memory mass storage device used mainly in portable electronic devices. The format was specified and the devices were first manufactured by SanDisk in 1994.
CompactFlash became one of the most successful of the e ...
was announced. CFast (also known as CompactFast) is based on the
Serial ATA
SATA (Serial AT Attachment) is a computer bus interface that connects host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. Serial ATA succeeded the earlier Parallel ATA (PATA) standard t ...
interface.
In November 2010, SanDisk, Sony and Nikon presented a next generation card format to the CompactFlash Association. The new format has a similar form factor to CF/CFast but is based on the
PCI Express
PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe or PCI-e, is a high-speed serial computer expansion bus standard, designed to replace the older PCI, PCI-X and AGP bus standards. It is the common ...
interface instead of Parallel ATA or Serial ATA. With potential read and write speeds of 1
Gbit/s
In telecommunications, data-transfer rate is the average number of bits ( bitrate), characters or symbols ( baudrate), or data blocks per unit time passing through a communication link in a data-transmission system. Common data rate units are mu ...
(125
MB/s
In telecommunications, data-transfer rate is the average number of bits ( bitrate), characters or symbols ( baudrate), or data blocks per unit time passing through a communication link in a data-transmission system. Common data rate units are mu ...
) and storage capabilities beyond 2
TiB, the new format is aimed at high-definition camcorders and high-resolution digital cameras, but the new cards are not backward compatible with either CompactFlash or CFast. The
XQD card
The XQD card is a memory card format primarily developed for flash memory cards. It uses PCI Express as a data transfer interface.
The format is targeted at high-definition camcorders and high-resolution digital cameras. It offers target read ...
format was officially announced by the CompactFlash Association in December 2011.
Description
![CompactFlash IDE Adaptor](https://upload.wikimedia.org/wikipedia/commons/f/f7/CompactFlash_IDE_Adaptor.jpeg)
There are two main subdivisions of CF cards, 3.3 mm-thick type I and 5 mm-thick type II (CF2). The type II slot is used by miniature hard drives and some other devices, such as the Hasselblad CFV Digital Back for the Hasselblad series of medium format cameras. There are four main card speeds: original CF, CF High Speed (using CF+/CF2.0), faster CF 3.0 standard and the faster CF 4.0 standard adopted as of 2007.
CompactFlash was originally built around
Intel
Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the developers of the x86 seri ...
's
NOR-based flash memory, but has switched to
NAND technology. CF is among the oldest and most successful formats, and has held a niche in the professional camera market especially well. It has benefited from both a better cost to memory-size ratio and, for much of the format's life, generally greater available capacity than other formats.
CF cards can be used directly in a PC Card slot with a plug adapter, used as an ATA (IDE) or PCMCIA storage device with a passive adapter or with a reader, or attached to other types of ports such as
USB
Universal Serial Bus (USB) is an industry standard that establishes specifications for cables, connectors and protocols for connection, communication and power supply (interfacing) between computers, peripherals and other computers. A broad ...
or
FireWire
IEEE 1394 is an interface standard for a serial bus for high-speed communications and isochronous real-time data transfer. It was developed in the late 1980s and early 1990s by Apple in cooperation with a number of companies, primarily Sony an ...
. As some newer card types are smaller, they can be used directly in a CF card slot with an adapter. Formats that can be used this way include
SD/
MMC, Memory Stick Duo,
xD-Picture Card
The xD-Picture Card is an obsolete form of flash memory card, used in digital cameras made by Olympus and Fujifilm during the 2000s. The xD in the xD-Picture Card stands for eXtreme Digital.
xD cards were manufactured with capacities of 16&nb ...
in a Type I slot and
SmartMedia
SmartMedia is an obsolete flash memory card standard owned by Toshiba, with capacities ranging from 2 MB to 128 MB. The format mostly saw application in the early 2000s in digital cameras and audio production. SmartMedia memory cards a ...
in a Type II slot, as of 2005. Some multi-card readers use CF for I/O as well.
The first CompactFlash cards had capacities of 2 to 10 megabytes.
Technical details
![Cf-card](https://upload.wikimedia.org/wikipedia/commons/b/b4/Cf-card.jpg)
The CompactFlash interface is a 50-pin subset of the 68-pin
PCMCIA connector. "It can be easily slipped into a passive 68-pin PCMCIA Type II to CF Type I adapter that fully meets PCMCIA electrical and mechanical interface specifications", according to compactflash.org. The interface operates, depending on the state of a mode pin on power-up, as either a 16-bit
PC Card (0x7FF address limit) or as an
IDE (PATA) interface.
Unlike the PC Card interface, no dedicated programming voltages (Vpp1 and Vpp2) are provided on the CompactFlash interface.
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 as if it were a
hard disk
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnet ...
. CF devices operate at 3.3
volt
The volt (symbol: V) is the unit of electric potential, electric potential difference (voltage), and electromotive force in the International System of Units (SI). It is named after the Italian physicist Alessandro Volta (1745–1827).
Defi ...
s or 5 volts, and can be swapped from system to system. CompactFlash supports
C-H-S and 28-bit
logical block addressing
Logical block addressing (LBA) is a common scheme used for specifying the location of blocks of data stored on computer storage devices, generally secondary storage systems such as hard disk drives. LBA is a particularly simple linear address ...
(CF 5.0 introduced support for LBA-48). CF cards with flash memory are able to cope with extremely rapid changes in temperature. Industrial versions of flash memory cards can operate at a range of −45 °C to +85 °C.
NOR-based flash has lower density than newer NAND-based systems, and CompactFlash is therefore the physically largest of the three memory card formats introduced in the early 1990s, being derived from the JEIDA/PCMCIA Memory Card formats. The other two are
Miniature Card
The Miniature Card or MiniCard is a flash or SRAM memory card standard first promoted by Intel in 1995. The card was backed by Advanced Micro Devices, Fujitsu and Sharp Electronics. They are no longer manufactured. The Miniature Card Implementers ...
(MiniCard) and
SmartMedia
SmartMedia is an obsolete flash memory card standard owned by Toshiba, with capacities ranging from 2 MB to 128 MB. The format mostly saw application in the early 2000s in digital cameras and audio production. SmartMedia memory cards a ...
(SSFDC). However, CF did switch to NAND type memory later. The
IBM Microdrive
The Microdrive is a registered trademark for miniature, 1-inch hard disks produced by IBM and Hitachi. These rotational media storage devices were designed to fit in CompactFlash (CF) Type II slots. The release of similar drives by other ...
format, later made by
Hitachi
() is a Japanese multinational corporation, multinational Conglomerate (company), conglomerate corporation headquartered in Chiyoda, Tokyo, Japan. It is the parent company of the Hitachi Group (''Hitachi Gurūpu'') and had formed part of the Ni ...
, implements the CF Type II interface, but is a
hard disk drive
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnet ...
(HDD) as opposed to solid-state memory.
Seagate also made CF HDDs.
Speed
CompactFlash
IDE (ATA) emulation speed is usually specified in "x" ratings, e.g. 8x, 20x, 133x. This is the same system used for
CD-ROM
A CD-ROM (, compact disc read-only memory) is a type of read-only memory consisting of a pre-pressed optical compact disc that contains data. Computers can read—but not write or erase—CD-ROMs. Some CDs, called enhanced CDs, hold both comput ...
s and indicates the maximum transfer rate in the form of a multiplier based on the original audio CD data transfer rate, which is 150 kB/s.
:
where ''R'' = transfer rate, ''K'' = speed rating. For example, 133x rating means transfer speed of: 133 × 150 kB/s = 19,950 kB/s ≈ 20 MB/s.
These are manufacturer speed ratings. Actual transfer speed may be higher, or lower, than shown on the card depending on several factors. The speed rating quoted is almost always the read speed, while write speed is often slower.
Solid state
For reads, the onboard controller first powers up the memory chips from standby. Reads are usually in parallel, error correction is done on the data, then transferred through the interface 16 bits at a time. Error checking is required due to soft read errors. Writes require powerup from standby, wear leveling calculation, a block erase of the area to be written to, ECC calculation, write itself (an individual memory cell read takes around 100 ns, a write to the chip takes 1ms+ or 10,000 times longer).
Because the USB 2.0 interface is limited to 35 MB/s and lacks bus mastering hardware, USB 2.0 implementation results in slower access.
Modern UDMA-7 CompactFlash Cards provide data rates up to 145 MB/s and require USB 3.0 data transfer rates.
A direct motherboard connection is often limited to 33 MB/s because IDE to CF adapters lack high speed ATA (66 MB/s plus) cable support. Power on from sleep/off takes longer than power up from standby.
Magnetic media
Many hard drives (often referred to by the trademarked name "
Microdrive
The Microdrive is a registered trademark for miniature, 1-inch hard disks produced by IBM and Hitachi. These rotational media storage devices were designed to fit in CompactFlash (CF) Type II slots. The release of similar drives by other ...
") typically spin at 3600 RPM, so rotational latency is a consideration, as is spin-up from standby or idle. Seagate's 8 GB ST68022CF drive spins up fully within a few revolutions but current drawn can reach up to 350 milliamps and runs at 40-50 mA mean current. Its average seek time is 8
ms and can sustain 9 MB/s read and write, and has an interface speed of 33 MB/s. Hitachi's 4 GB Microdrive is 12 ms seek, sustained 6 MB/s.
Capacities and compatibility
The CF 5.0 Specification supports capacities up to 128 PiB using 48-bit
logical block addressing
Logical block addressing (LBA) is a common scheme used for specifying the location of blocks of data stored on computer storage devices, generally secondary storage systems such as hard disk drives. LBA is a particularly simple linear address ...
(LBA). Prior to 2006, CF drives using magnetic media offered the highest capacities (up to 8
GiB
The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable unit ...
). Now there are solid-state cards with higher capacities (up to 512 GB).
As of 2011,
solid-state drives
A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory, and functioning as secondary storage in the hierarchy of computer storage. It i ...
(SSDs) have supplanted both kinds of CF drive for large capacity requirements.
Solid state capacities
SanDisk
SanDisk is a brand for flash memory products, including memory cards and readers, USB flash drives, solid-state drives, and digital audio players, manufactured and marketed by Western Digital. The original company, SanDisk Corporation was acquir ...
announced its 16 GB ''Extreme III'' card at the
photokina
Photokina (rendered in the promoters' branding as "photokina") is a trade fair held in Europe for the photographic and imaging industries. It is the world's largest such trade fair. The first Photokina was held in Cologne, Germany, in 1950, a ...
trade fair, in September, 2006. That same month,
Samsung
The Samsung Group (or simply Samsung) ( ko, 삼성 ) is a South Korean multinational manufacturing conglomerate headquartered in Samsung Town, Seoul, South Korea. It comprises numerous affiliated businesses, most of them united under the ...
announced 16, 32 and 64 GB CF cards. Two years later, in September, 2008,
PRETEC announced 100 GB cards.
Magnetic media capacities
Seagate announced a 5 GB "1-inch hard drive" in June, 2004, and an 8 GB version in June, 2005.
Use in place of a hard disk drive
![CompactFlash to SATA adapter with card](https://upload.wikimedia.org/wikipedia/commons/5/5c/CompactFlash_to_SATA_adapter_with_card.jpg)
In early 2008, the CFA demonstrated CompactFlash cards with a built in
SATA
SATA (Serial AT Attachment) is a computer bus interface that connects host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. Serial ATA succeeded the earlier Parallel ATA (PATA) standard t ...
interface. Several companies make adapters that allow CF cards to be connected to
PCI,
PCMCIA,
IDE and
SATA
SATA (Serial AT Attachment) is a computer bus interface that connects host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. Serial ATA succeeded the earlier Parallel ATA (PATA) standard t ...
connections, allowing a CF card to act as a
solid-state drive
A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory, and functioning as secondary storage in the hierarchy of computer storage. It is a ...
with virtually any operating system or BIOS, and even in a
RAID
Raid, RAID or Raids may refer to:
Attack
* Raid (military), a sudden attack behind the enemy's lines without the intention of holding ground
* Corporate raid, a type of hostile takeover in business
* Panty raid, a prankish raid by male college ...
configuration.
CF cards may perform the function of the master or slave drive on the IDE bus, but have issues sharing the bus. Moreover, late-model cards that provide
DMA (using UDMA or MWDMA) may present problems when used through a passive adapter that does not support DMA.
Reliability
Original PC Card memory cards used an internal battery to maintain data when power was removed. The rated life of the battery was the only reliability issue. CompactFlash cards that use flash memory, like other flash-memory devices, are rated for a limited number of erase/write cycles for any "block." While NOR flash has higher endurance, ranging from 10,000 to 1,000,000, they haven't been adapted for memory card usage. Most mass storage usage flash are NAND based. NAND flash were being scaled down to 16 nm. They are usually rated for 500 to 3,000 write/erase cycles per block before hard failure.
This is less reliable than magnetic media. ''Car PC Hacks''
[''Car PC hacks'', Damien Stolarz, 2005, Farnham:O’Reilly Media, Sebastopol, CA, USA, ] suggests disabling the Windows swap file and using its
Enhanced Write Filter
Enhanced Write Filter (or EWF) is a component of Windows XP Embedded and Windows Embedded Standard 7 which stores Volume (computing), volume changes on another medium instead of applying them to the original volume. EWF allows the writes to be dis ...
(EWF) to eliminate unnecessary writes to flash memory. Additionally, when formatting a flash-memory drive, the Quick Format method should be used, to write as little as possible to the device.
Most CompactFlash flash-memory devices limit wear on blocks by varying the physical location to which a block is written. This process is called
wear leveling Wear leveling (also written as wear levelling) is a technique Wear leveling techniques for flash memory systems. for prolonging the service life of some kinds of erasable computer storage media, such as flash memory, which is used in solid-state d ...
. When using CompactFlash in ATA mode to take the place of the
hard disk drive
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnet ...
, wear leveling becomes critical because low-numbered blocks contain tables whose contents change frequently. Current CompactFlash cards spread the wear-leveling across the entire drive. The more advanced CompactFlash cards will move data that rarely changes to ensure all blocks wear evenly.
NAND flash memory is prone to frequent soft read errors.
The CompactFlash card includes
error checking and correcting
In information theory and coding theory with applications in computer science and telecommunication, error detection and correction (EDAC) or error control are techniques that enable reliable delivery of digital data over unreliable communi ...
(ECC) that detects the error and re-reads the block. The process is transparent to the user, although it may slow data access.
As a flash memory device is
solid-state
Solid state, or solid matter, is one of the four fundamental states of matter.
Solid state may also refer to:
Electronics
* Solid-state electronics, circuits built of solid materials
* Solid state ionics, study of ionic conductors and their use ...
, it is less affected by shock than a spinning disk.
The possibility for electrical damage from upside-down insertion is prevented by asymmetrical side slots, assuming that the host device uses a suitable connector.
Power consumption and data transfer rate
Small cards consume around 5% of the power required by small disk drives and still have reasonable transfer rates of over 45 MB/s for the more expensive 'high-speed' cards. However, the manufacturer's warning on the flash memory used for
ReadyBoost
ReadyBoost (codenamed EMD) is a disk caching software component developed by Microsoft for Windows Vista and included in later versions of Windows. ReadyBoost enables NAND memory mass storage CompactFlash, SD card, and USB flash drive devices t ...
indicates a current draw in excess of 500 mA.
File systems
CompactFlash cards for use in consumer devices are typically formatted as
FAT12
File Allocation Table (FAT) is a file system developed for personal computers. Originally developed in 1977 for use on floppy disks, it was adapted for use on hard disks and other devices. It is often supported for compatibility reasons by ...
(for media up to 16 MB),
FAT16
File Allocation Table (FAT) is a file system developed for personal computers. Originally developed in 1977 for use on floppy disks, it was adapted for use on hard disks and other devices. It is often supported for compatibility reasons by ...
(for media up to 2 GB, sometimes up to 4 GB) and
FAT32
File Allocation Table (FAT) is a file system developed for personal computers. Originally developed in 1977 for use on floppy disks, it was adapted for use on hard disks and other devices. It is often supported for compatibility reasons by ...
(for media larger than 2 GB). This lets the devices be read by personal computers but also suits the limited processing ability of some consumer devices such as
camera
A camera is an Optics, optical instrument that can capture an image. Most cameras can capture 2D images, with some more advanced models being able to capture 3D images. At a basic level, most cameras consist of sealed boxes (the camera body), ...
s.
There are varying levels of compatibility among FAT32-compatible cameras, MP3 players, PDAs, and other devices. While any device that claims FAT32-capability should read and write to a FAT32-formatted card without problems, some devices are tripped up by cards larger than 2 GB that are completely unformatted, while others may take longer to apply a FAT32 format.
The way many digital cameras update the file system as they write to the card creates a FAT32 bottleneck. Writing to a FAT32-formatted card generally takes a little longer than writing to a FAT16-formatted card with similar performance capabilities. For instance, the
Canon EOS 10D
The Canon EOS 10D is a discontinued 6.3-megapixel semi-professional digital SLR camera, initially announced on 27 February 2003. It replaced the EOS D60, which is also a 6.3-megapixel digital SLR camera. It was succeeded by the EOS 20D in Augu ...
writes the same photo to a FAT16-formatted 2 GB CompactFlash card somewhat faster than to a same speed 4 GB FAT32-formatted CompactFlash card, although the memory chips in both cards have the same write speed specification. Although FAT16 is more wasteful of disk space with its larger clusters, it works better with the write strategy that flash memory chips require.
The cards themselves can be formatted with any type of file system such as
Ext
Ext, ext or EXT may refer to:
* Ext functor, used in the mathematical field of homological algebra
* Ext (JavaScript library), a programming library used to build interactive web applications
* Exeter Airport (IATA airport code), in Devon, England
...
,
JFS,
NTFS
New Technology File System (NTFS) is a proprietary journaling file system developed by Microsoft. Starting with Windows NT 3.1, it is the default file system of the Windows NT family. It superseded File Allocation Table (FAT) as the preferred fil ...
, or by one of the dedicated
flash file system A flash file system is a file system designed for storing files on flash memory–based storage devices. While flash file systems are closely related to file systems in general, they are optimized for the nature and characteristics of flash ...
s. It can be divided into partitions as long as the host device can read them. CompactFlash cards are often used instead of hard drives in embedded systems,
dumb terminal
A computer terminal is an electronic or electromechanical hardware device that can be used for entering data into, and transcribing data from, a computer or a computing system. The teletype was an example of an early-day hard-copy terminal a ...
s and various small form-factor PCs that are built for low noise output or power consumption. CompactFlash cards are often more readily available and smaller than purpose-built
solid-state drive
A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory, and functioning as secondary storage in the hierarchy of computer storage. It is a ...
s and often have faster
seek time Higher performance in hard disk drives comes from devices which have better performance characteristics. These performance characteristics can be grouped into two categories: access time and data transfer time (or rate).
Access time
The ''access ...
s than hard drives.
CF+ and CompactFlash specification revisions
When CompactFlash was first being standardized, even full-sized hard disks were rarely larger than 4 GB in size, and so the limitations of the ATA standard were considered acceptable. However, CF cards manufactured after the original Revision 1.0 specification are available in capacities up to 512 GB. While the current revision 6.0 works in
TA mode,
future revisions are expected to implement
SATA
SATA (Serial AT Attachment) is a computer bus interface that connects host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. Serial ATA succeeded the earlier Parallel ATA (PATA) standard t ...
mode.
* CompactFlash Revision 1.0 (1995), 8.3 MB/s (PIO mode 2), support for up to 128 GB storage space.
* CompactFlash+ aka CompactFlash I/O (1997)
* CF+ and CompactFlash Revision 2.0 (2003) added an increase in speed to 16.6 MB/s data-transfer (PIO mode 4). At the end of 2003,
DMA 33 transfers were added as well, available since mid-2004.
* CF+ and CompactFlash Revision 3.0 (2004) added support for up to a 66 MB/s data transfer rate (
UDMA
Udma is a census town in Kasaragod district in the Indian States and territories of India, state of Kerala.
Demographics
As of 2011 India census, Udma census town had population of 8,115 which constitutes 3,593 males and 4,522 females. Udma c ...
66), 25 MB/s in PC Card mode, added password protection, along with a number of other features. CFA recommends usage of the FAT32 filesystem for storage cards larger than 2 GB.
* CF+ and CompactFlash Revision 4.0 (2006) added support for IDE Ultra DMA Mode 6 for a maximum data transfer rate of 133 MB/s (UDMA 133).
* CF+ and CompactFlash Revision 4.1 (2007) added support for Power Enhanced CF Storage Cards.
* CompactFlash Revision 5.0 (2010) added a number of features, including 48-bit addressing (supporting 128 petabyte of storage), larger block transfers of up to 32 megabytes, quality-of-service and video performance guarantees, and other enhancements
* CompactFlash Revision 6.0 (November 2010) added UltraDMA Mode 7 (167 MB/s), ATA-8/ACS-2 sanitize command,
TRIM
Trim or TRIM may refer to:
Cutting
* Cutting or trimming small pieces off something to remove them
** Book trimming, a stage of the publishing process
** Pruning, trimming as a form of pruning often used on trees
Decoration
* Trim (sewing), or ...
and an optional card capability to report the
operating temperature
An operating temperature is the allowable temperature range of the local ambient environment at which an electrical or mechanical device operates. The device will operate effectively within a specified temperature range which varies based on the de ...
range of the card.
CE-ATA
CE-ATA is a serial MMC-compatible interface based on the
MultiMediaCard standard.
CFast
![CFast Kontakte (cropped)](https://upload.wikimedia.org/wikipedia/commons/8/88/CFast_Kontakte_%28cropped%29.jpg)
A variant of CompactFlash known as CFast is based on the
Serial ATA
SATA (Serial AT Attachment) is a computer bus interface that connects host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. Serial ATA succeeded the earlier Parallel ATA (PATA) standard t ...
(SATA) interface, rather than the
Parallel ATA/IDE (PATA) bus for which all previous versions of CompactFlash are designed. CFast is also known as CompactFast.
CFast 1.0/1.1 supports a higher maximum transfer rate than current CompactFlash cards, using
SATA 2.0
SATA (Serial AT Attachment) is a computer bus interface that connects host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. Serial ATA succeeded the earlier Parallel ATA (PATA) standard t ...
(300 MB/s) interface, while PATA is limited to 167 MB/s using
UDMA 7.
CFast cards are not physically or electrically compatible with CompactFlash cards. However, since SATA can emulate the PATA command protocol, existing CompactFlash software drivers can be used, although writing new drivers to use
AHCI
The Advanced Host Controller Interface (AHCI) is a technical standard defined by Intel that specifies the register-level interface of Serial ATA (SATA) host controllers in a non-implementation-specific manner in its motherboard chipsets.
The ...
instead of PATA emulation will almost always result in significant performance gains. CFast cards use a female
7-pin SATA data connector, and a female 17-pin power connector, so an adaptor is required to connect CFast cards in place of standard SATA hard drives which use male connectors.
The first CFast cards reached the market in late 2009. At
CES 2009, Pretec showed a 32 GB CFast card and announced that they should reach the market within a few months. Delock began distributing CFast cards in 2010, offering several card readers with
USB 3.0
USB 3.0, released in November 2008, is the third major version of the Universal Serial Bus (USB) standard for interfacing computers and electronic devices. Among other improvements, USB 3.0 adds the new transfer rate referred to as '' ...
and
eSATAp
In computing, eSATAp (also known as Power over eSATA, Power eSATA, eSATA/USB Combo, eSATA USB Hybrid Port/EUHP) is a combination connection for external storage devices. An eSATA or USB device can be plugged into an eSATAp port. The socke ...
(power over eSATA) ports to support CFast cards.
Seeking higher performance and still keeping a compact storage format, some of the earliest adoptors of CFast cards were in the gaming industry (used in slot machines), as a natural evolution from the by then well-established CF cards. Current gaming industry supporters of the format include both specialist gaming companies (e.g.
Aristocrat Leisure
Aristocrat Leisure Limited is an Australian gambling machine manufacturer, which has its administrative and research headquarters in the Sydney suburb of North Ryde. It has marketing and development offices in South Africa, Russia, and the Uni ...
) and OEMs such as Innocore (now part of
Advantech Co., Ltd.).
The CFast 2.0 specification was released in the second quarter of 2012, updating the electrical interface to
SATA 3.0 (600 MB/s). As of 2014, the only product employing CFast 2.0 cards was the
Arri
The Arri Group () is a German manufacturer of motion picture film equipment. Based in Munich, the company was founded in 1917. It produces professional motion picture cameras, lenses, lighting and post-production equipment. Hermann Simon menti ...
Amira digital production camera, allowing frame rates of up to 200 fps; a CFast 2.0 adapter for the
Arri Alexa/XT camera was also released.
On 7 April 2014,
Blackmagic Design
Blackmagic Design Pty Ltd. is an Australian digital cinema company and hardware manufacturer based in Port Melbourne, Victoria, Australia. It designs and manufactures broadcast and cinema hardware, most notably high-end digital-movie camer ...
announced the URSA cinema camera, which records to CFast media.
On 8 April 2015,
Canon Inc.
is a Japanese multinational corporation headquartered in Ōta, Tokyo, Japan, specializing in optical, imaging, and industrial products, such as lenses, cameras, medical equipment, scanners, printers, and semiconductor manufacturing equipment.< ...
announced the
XC10 video camera, which also makes use of CFast cards. Blackmagic Design also announced that its URSA Mini will use CFast 2.0.
As of October 2016, there are a growing number of cameras, video recorders, and audio recorders that use the faster data rates offered by CFast media.
As of 2017, in the wider embedded electronics industry, transition from CF to CFast is still relatively slow, probably due to hardware cost considerations and some inertia (familiarity with CF) and because a significant part of the industry is satisfied with the lower performance provided by CF cards, thus having no reason to change. A strong incentive to change to CFast for embedded electronics companies using designs based on Intel PC architecture is the fact that Intel has removed native support for the (P)ATA interface a few design platforms ago and the older CPU/PCH generations now have end-of-life status.
CFexpress
In September 2016, the CompactFlash Association announced a new standard based on PCIe 3.0 and NVMe,
CFexpress
CFexpress is a standard for removable media cards proposed by the CompactFlash Association (CFA). The standard uses PCIe 3.0 interface with 1 to 4 lanes where 1 GB/s data can be provided per lane. NVM Express is also supported to provide low overh ...
. In April 2017, the version 1.0 of the CFexpress specification was published, with support for two PCIe 3.0 lanes in an XQD form-factor for up to 2 GB/s.
Type I and Type II
The only physical difference between the two types is that Type I devices are 3.3 mm thick while Type II devices are 5 mm thick. Electrically, the two interfaces are the same except that Type I devices are permitted to draw up to 70 mA supply current from the interface, while type II devices may draw up to 500 mA.
Most Type II devices are Microdrive devices (see
below), other miniature hard drives, and adapters, such as a popular adapter that takes Secure Digital cards. A few flash-based Type II devices were manufactured, but Type I cards are now available in capacities that exceed CF HDDs. Manufacturers of CompactFlash cards such as Sandisk, Toshiba, Alcotek and Hynix offer devices with Type I slots only. Some of the latest
DSLR
A digital single-lens reflex camera (digital SLR or DSLR) is a digital camera that combines the optics and the mechanisms of a single-lens reflex camera with a digital imaging sensor.
The reflex design scheme is the primary difference between a ...
cameras, like the
Nikon D800
The Nikon D800 is a 36.3-megapixel professional-grade full-frame digital single-lens reflex camera produced by Nikon Corporation. It was given a Gold Award by Digital Photography Review.
It was officially announced on February 7, 2012 and went o ...
, have also dropped Type II support.
Microdrives
![MicroDrive1GB](https://upload.wikimedia.org/wikipedia/commons/3/3b/MicroDrive1GB.jpg)
Microdrive was a brand of tiny
hard disk
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnet ...
s—about 25 mm (1 inch) wide—in a CompactFlash Type II package. The first was developed and released in 1999 by
IBM, with a capacity of 170 MB. IBM sold its disk drive division, including the Microdrive trademark, to
Hitachi
() is a Japanese multinational corporation, multinational Conglomerate (company), conglomerate corporation headquartered in Chiyoda, Tokyo, Japan. It is the parent company of the Hitachi Group (''Hitachi Gurūpu'') and had formed part of the Ni ...
in 2002. Comparable hard disks were also made by other vendors, such as Seagate and Sony. They were available in capacities of up to 8 GB but have been superseded by flash memory in cost, capacity, and reliability, and are no longer manufactured.
As mechanical devices, CF HDDs drew more current than flash memory's 100 mA maximum. Early versions drew up to 500 mA, but more recent ones drew under 200 mA for reads and under 300 mA for writes. (Some devices used for high speed—such as ReadyBoost, which had no low-power standby mode—exceeded the 500 mA maximum of the Type II standard.) CF HDDs were also susceptible to damage from physical shock or temperature changes. However, CF HDDs had a longer lifespan of write cycles than early flash memories.
The
iPod mini
The iPod Mini (stylized and marketed as the iPod mini) is a discontinued, smaller digital audio player that was designed and marketed by Apple Inc. While it was sold, it was the midrange model in Apple's iPod product line. It was announced o ...
,
Nokia N91
The Nokia N91 is a smartphone produced by Nokia as part of their Nseries line of portable devices. It was announced on April 27, 2005 along with N70 and N90 as the first three Nseries devices. The N91 ran on Symbian-based S60 3rd Edition (the ...
,
iriver H10
The H10 is a series of portable audio players developed by iRiver, coming in multiple capacities and sizes. The player first went on sale in South Korea in December 2004 and rolled out internationally soon afterwards. The H10 series are hard di ...
(5 or 6 GB model),
LifeDrive
The LifeDrive is a Palm OS-based handheld personal digital assistant device that was produced by PalmOne, a former incarnation of Palm, Inc. The device was PalmOne's first and only foray into the "Mobile Manager" device category. As its name sugge ...
, and
Rio Carbon
The Rio Carbon is a line of digital audio players that was produced by the now defunct Rio from 2004 to 2005. It was similar in size, capacity, and cost with Apple's iPod Mini which debuted earlier the same year. This was Rio's second player to us ...
used a Microdrive to store data.
Compared to other portable storage
* CompactFlash cards that use flash memory are more rugged than some hard drive solutions because they are solid-state. (See also
Reliability
Reliability, reliable, or unreliable may refer to:
Science, technology, and mathematics Computing
* Data reliability (disambiguation), a property of some disk arrays in computer storage
* High availability
* Reliability (computer networking), a ...
above.) Separately, CompactFlash cards are thicker than other card formats, which may render them less susceptible to breakage from harsh treatment.
* As CompactFlash cards support the IDE/ATA command protocol with the host device, a passive adapter lets them function as the
hard disk drive
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnet ...
of a
personal computer
A personal computer (PC) is a multi-purpose microcomputer whose size, capabilities, and price make it feasible for individual use. Personal computers are intended to be operated directly by an end user, rather than by a computer expert or tec ...
, as described
above.
* CompactFlash does not have any built in
DRM
DRM may refer to:
Government, military and politics
* Defense reform movement, U.S. campaign inspired by Col. John Boyd
* Democratic Republic of Madagascar, a former socialist state (1975–1992) on Madagascar
* Direction du renseignement milita ...
or cryptographic features found on some
USB flash drive
A USB flash drive (also called a thumb drive) is a data storage device that includes flash memory with an integrated USB interface. It is typically removable, rewritable and much smaller than an optical disc. Most weigh less than . Since firs ...
s and other card formats. The absence of such features contributes to the openness of the standard, as card standards with such features may be subject to restrictive licensing agreements.
* The initial CompactFlash specification envisaged a higher maximum capacity than other card formats. For this reason, many early CompactFlash host devices are usable with modern multi-gigabyte memories, where users of other families such as
Secure Digital
Secure Digital, officially abbreviated as SD, is a proprietary format, proprietary non-volatile memory, non-volatile Flash memory, flash memory card format developed by the SD Association, SD Association (SDA) for use in portable devices.
The s ...
have had to migrate to SDHC and SDXC.
* CompactFlash lacks the mechanical write protection switch that some other devices have, as seen in a
comparison of memory cards
This table provides summary of comparison of various flash memory cards, .
Common information
:''unless otherwise indicated, all images to scale''
Physical details
Note that a memory card's dimensions are determined while holding the card w ...
.
* CompactFlash is physically larger than other card formats. This limits its use, especially in miniature consumer devices where internal space is limited, such as
point-and-shoot
A point-and-shoot camera, also known as a compact camera and sometimes abbreviated to P&S, is a still camera designed primarily for simple operation. Most use focus free lenses or autofocus for focusing, automatic systems for setting the exposu ...
digital cameras. (An offsetting benefit of larger size is that the card is easier to insert and remove, and harder to misplace.)
Counterfeiting
The marketplace for CompactFlash is extensive and includes
counterfeits. Off-brand or counterfeit cards may be mislabeled, might not contain the actual amount of memory their controllers report to the host device, and may use types of memory that are not rated for the number of erase/rewrite cycles that the purchaser expects.
Other devices in the CF form factor
![Cf io](https://upload.wikimedia.org/wikipedia/commons/5/56/Cf_io.jpg)
Since CompactFlash interface is electrically identical to the 16-bit
PC Card, the CompactFlash form factor is also used for a variety of Input/Output and interface devices. Many standard PC cards have CF counterparts, some examples include:
*
Barcode scanner
A barcode reader is an optical scanner that can read printed barcodes, decode the data contained in the barcode to a computer. Like a flatbed scanner, it consists of a light source, a lens and a light sensor for translating optical impulses int ...
*
Bluetooth
Bluetooth is a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks (PANs). In the most widely used mode, transmission power is limi ...
*
Digital Camera
A digital camera is a camera that captures photographs in digital memory. Most cameras produced today are digital, largely replacing those that capture images on photographic film. Digital cameras are now widely incorporated into mobile device ...
*
Ethernet
Ethernet () is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 198 ...
*
GPS
The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t ...
*
Magnetic stripe
The term digital card can refer to a physical item, such as a memory card on a camera, or, increasingly since 2017, to the digital content hosted
as a virtual card or cloud card, as a digital virtual representation of a physical card. They share ...
reader
*
Microdrive
The Microdrive is a registered trademark for miniature, 1-inch hard disks produced by IBM and Hitachi. These rotational media storage devices were designed to fit in CompactFlash (CF) Type II slots. The release of similar drives by other ...
*
Modem
A modulator-demodulator or modem is a computer hardware device that converts data from a digital format into a format suitable for an analog transmission medium such as telephone or radio. A modem transmits data by Modulation#Digital modulati ...
and
GSM
The Global System for Mobile Communications (GSM) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation ( 2G) digital cellular networks used by mobile devices such ...
Modem, including
GPRS,
CDMA2000 and
EDGE
Edge or EDGE may refer to:
Technology Computing
* Edge computing, a network load-balancing system
* Edge device, an entry point to a computer network
* Adobe Edge, a graphical development application
* Microsoft Edge, a web browser developed ...
* Readers for various other
Flash media
Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates. Both use t ...
*
RFID
Radio-frequency identification (RFID) uses electromagnetic fields to automatically identify and track tags attached to objects. An RFID system consists of a tiny radio transponder, a radio receiver and transmitter. When triggered by an electromag ...
*
Sampler (musical instrument)
A sampler is an electronic or digital musical instrument which uses sound recordings (or " samples") of real instrument sounds (e.g., a piano, violin, trumpet, or other synthesizer), excerpts from recorded songs (e.g., a five-second bass guita ...
*
Serial port
In computing, a serial port is a serial communication interface through which information transfers in or out sequentially one bit at a time. This is in contrast to a parallel port, which communicates multiple bits simultaneously in parallel. ...
and
USB 1.1
Universal Serial Bus (USB) is an industry standard that establishes specifications for cables, connectors and protocols for connection, communication and power supply (interfacing) between computers, peripherals and other computers. A broad ...
host adapters
*
Super VGA
Super VGA (SVGA) is a broad term that covers a wide range of computer display standards that extended IBM's Video Graphics Array, VGA specification.
When used as shorthand for a resolution, as VGA and XGA often are, SVGA refers to a resolution of ...
display adapter
*
Wi-Fi
Wi-Fi () is a family of wireless network protocols, based on the IEEE 802.11 family of standards, which are commonly used for local area networking of devices and Internet access, allowing nearby digital devices to exchange data by radio wave ...
Pinout
Shown looking card.
See also
*
Comparison of memory cards
This table provides summary of comparison of various flash memory cards, .
Common information
:''unless otherwise indicated, all images to scale''
Physical details
Note that a memory card's dimensions are determined while holding the card w ...
*
ExpressCard
*
SD Association
*
Microdrive
The Microdrive is a registered trademark for miniature, 1-inch hard disks produced by IBM and Hitachi. These rotational media storage devices were designed to fit in CompactFlash (CF) Type II slots. The release of similar drives by other ...
*
PC Card
*
Random-access memory
Random-access memory (RAM; ) is a form of computer memory that can be read and changed in any order, typically used to store working Data (computing), data and machine code. A Random access, random-access memory device allows data items to b ...
*
XQD card
The XQD card is a memory card format primarily developed for flash memory cards. It uses PCI Express as a data transfer interface.
The format is targeted at high-definition camcorders and high-resolution digital cameras. It offers target read ...
References
External links
CompactFlash AssociationRob Galbraith DPI: CF Performance DatabaseCompactFlash connector description and pin layoutCompactFlash Connector Schematic and complete Pinout
{{DEFAULTSORT:Compactflash
American inventions
Computer memory
Solid-state computer storage media