CompactFlash

There are two types of cards: CompactFlash Type I and Type II. The Type II version of the cards was created exclusively for Microdrive miniature hard drives and can be considered obsolete today. CompactFlash Type I cards are 42 mm by 36 mm, thickness is 3.3 mm, and CompactFlash Type II is 5 mm. CompactFlash Type I cards can be inserted into slots of both sizes, CompactFlash Type II - only into a slot for CompactFlash Type II.

The CompactFlash interface has a 50-pin connector — an abbreviated set of signal lines of the PCMCIA connector, which has 68 pins (like a 16-bit PC Card with an address limit of 0x7FF). A CompactFlash memory card can be inserted into the PCMCIA Type II slot using a passive adapter. Also, using a passive adapter, it is possible to connect CompactFlash to the IDE (ATA) disk drives (the layout of these interfaces does not completely coincide). Connecting to serial interfaces ( USB , FireWire , SATA ) is possible when using an active adapter.

Some multi-card readers use the CompactFlash interface for I / O as well. Like CompactFlash, some new types of cards that are smaller than its size are provided for their use in the CompactFlash card slot through the adapter. Formats that can be used in this way include SD / MMC, Memory Stick Duo, xD-Picture Card in slot Type I and SmartMedia in slot Type II (as of 2005).

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  Adapter with Secure Digital to CompactFlash

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  Internal CF Adapter - IDE

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  CF Adapter - IDE for installation in the expansion slot of the system unit

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  CF internal adapter - SATA

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  External USB multi card reader with CF slot

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  EDGE modem for connection via CF interface

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  GPS receiver for connection via CF interface

The specification for this format is the Association CompactFlash ^[2] .

The standard specifies:

• dimensions and mechanical properties of CompactFlash devices, as well as the types of connectors used;
• electrical interface (bus signals, bus cycles, and socket pinout);
• metaformat;
• software model of CompactFlash devices;
• adapters for connecting CompactFlash devices to the PCMCIA bus.

Specification history

• CompactFlash 1.0 (1995).
• CompactFlash + (1997).
• CompactFlash 2.0 (2003). Speed ​​up to 16.6 MB / s.
• CompactFlash 3.0 (2004). Speed ​​up to 66 MB / s.
• CompactFlash 4.0 (2006). Speed ​​up to 133 MB / s. Up to 137 gigabytes.
• CompactFlash 5.0 (2010). Speed ​​up to 133 MB / s. Up to 144 petabytes. ^{[3] [4]}
• CompactFlash 6.0 (2010). Speed ​​up to 167 MB / s ^[5]

CFast

Further development of the standard were CFast cards on the SATA bus. CFast cards are electrically and physically incompatible with CF, have a standard 7-pin SATA interface connector, and a 17-pin power supply (other than SATA). The first maps and devices for working with them were presented on the market in 2010. At the beginning of 2013, maps of this format were not widely used in user devices; however, they are used in some “ embedded systems ” as the only data carrier and can be installed via an additional adapter into a regular computer instead of a hard disk.

CFast 2.0

The second generation of cards.

3400x 510MB / s ^[6]

Benefits

• Capacity CF is one of the most capacious flash memory cards . Firms Pretec and SanDisk produce cards with a capacity of 256 gigabytes. Lexar and Kingston - 512 GB ^[7]
• Speed CF is a very fast memory card, its write / read speed is higher than other formats of flash memory cards , so, for example, in phototechnics with CF you can shoot in long batches without fear of a buffer overflow. In 2012, Lexar drives with CompactFlash interface with 1000x read speed (150MB / s) appeared on the market. ^[eight]
• Lack of DRM . CF is a universal memory card, not just for publishing content.
• Compatibility . With the help of a passive adapter, CF cards can be connected to IDE ports of computers, and CFast to SATA ports.

Disadvantages

• Significant size. Now CF - the largest memory cards in the mass market.
• An unfortunate design, in which in some cases (involuntary misalignment, an attempt to insert a card in the wrong way, wear on the reader's guides, etc.), bending or breaking of the contacts of the reader is possible (this is fixed in CFast). There is no clear fixation of the card in the reader, which, together with a sufficiently large effort to install and remove the card, forces the manufacturers of compatible devices to supply the card slot with additional mechanical devices that facilitate these processes.

The card speed is usually referred to as “x” (multiplication sign) and a number is placed in front of it, meaning how many times the card’s reading speed is greater than 150 (KB / s) (this is the minimum and standard CD reading speed, with the minimum standard spindle speeds of the drive mechanism; this speed is usually denoted 1x). The table shows the standard values ​​of the card speed and the corresponding maximum data transfer rate defined by the standard.

• Microdrive
• Disk on Module
• CFexpress

• CompactFlash Association (eng.)