Talk:CompactFlash

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[edit] Capacity

Hey, guys... I don't have the source with me to prove this at the moment... But I distinctly remember buying an 8 gig CF card in late 2001... It was just ridiculously expensive... If someone could find a source for me, that'd be great. —Preceding unsigned comment added by 146.151.49.74 (talk) 02:13, 30 January 2008 (UTC)

[edit] Wear

The article points out CF appears similar to a hard drive. Should it point out that it doesn't support as many write cycles as a hard drive over its life?

jffs (Journaled Flash FilSystem) has a feature that spreads write cycles over the whole device (generally avoiding to rewrite the same block over itself); this grately reduces the chances of faliure on amy particula block of the flash device. Does the ATA interface embedded on CF devices make similar arrangements to reduce the possibility of faliure o a particular block being rewritten very often ?

Sooner or later, both media are vulnerable to occurrence of bad sectors(or blocks). Numbers of insertion/removal counts written in products specifications do mean that ratio of bad sectors is likely to increase when used beyond those numbers written, not that the products themselves become entirely useless at once.-ComSpex 08:54, 16 April 2006 (UTC)

See wear levelling DHR 04:22, 17 April 2006 (UTC)

Thank you, DHR. That's what I've looked around for.-ComSpex 08:09, 17 April 2006 (UTC)

[edit] Moving parts? Altitude limits?

Another difference between Compact Flash and Microdrive is that CF cards have --- I believe --- no moving parts. I've also heard that Microdrive does not work at high altitudes, due to insufficient air to float the disk head. Can anyone confirm these?

The Hitachi support site (with which company IBM has a partnership) quotes the operational altitude of Microdrives as -300 to 3000 meters, however I was unable to find confirmational specifications on the IBM site. Anecdotal evidence seems to support this (try Googling for Everest and Microdrive, for instance).

[edit] current records

What is the current record for (1) the largest capacity CF card (2) the fastest CF card (3) the smallest capacity CF card.

Can CF-I cards be used in CF-II slots?

You can use the CF I card in a CF II slot.

Chris Thames mavroxur@hotmail.com

Are the capacities in gigabytes or gibibytes?

AxelBoldt 21:27, 22 Nov 2004 (UTC)

Ok, I figured out the answers and put them into the article. AxelBoldt 23:52, 22 Nov 2004 (UTC)

I've seen CF cards as small as 4 megabytes, supplied as 'starter' cards with low-end HP digital cameras.

[edit] I & II

What the difference between type I and type II?

sorry, I am new, and don't know how to post a new question, so I just add my question in the answer part.

The difference between CF I and CFII is the physical thickness of the card. The electrical interface is the same (both in mechanical and signaling). CF I cards are 3.3mm thick, and CF II's are 5mm thick. For example, a CF I card will fit in a CF II slot, but not the other way around.

Chris Thames - mavroxur@hotmail.com

[edit] "Dominant Design question!"

As of late 2005. Do you think there's a dominant design in the flash memory market? Is there a dominant player (SanDisk, may be?) in the market? or the battle for the dominant design is still going on, and no single company has its design chosen as the dominant design yet?

[edit] 12 gigs?

"As of 2005, CompactFlash cards are available in capacities from about 8 megabytes to about 12 gigabytes." (Last sentence of description paragraph). I think the maximum number is around 4-6 gigs, or else Microdrives wouldn't exist :-)

[edit] This Needs a Rewrite

This whole entry needs a rewrite. It reads too much like an advertisement for SanDisk. The prose style needs work too.

There are ambiguities that need firming up -- "...about 8 megabytes to about 12 gigabytes...". Though I have found a company (Pretec) that lists a 12GB CompactFlash device (with solid-state memory, not a micro-drive). Also, several technical terms need links to their corresponding Wikipedia article, and some should be called by their IEEE name (as-in "FireWire" should at least mention IEEE-1394).

Can someone explain a use for a CompactFlash card that is not a storage device? Is there any item on the market that uses a CompactFlash card as Main Memory -- that is to say, computational space?

Charles Gaudette 17:05, 14 March 2006 (UTC)

There are lots of non-storage CF cards. See the article section "Other devices conforming to the CF standard". It seems unfortunate that this section appears to be an afterthought. I think the idea of supporting multiple types of devices should be very near the start. DHR 19:48, 21 March 2006 (UTC)

[edit] CF vs CF+ vs ATA

I'd like to know if certain disk drives will work in my PDA. The PDA has a CF II slot. This is supposed to support IDE (electircally). The disk drive is mechanically CF II but claims ATA (as opposed to CF) conformance. What does that mean? To me, ATA is a kind of IDE. There is a hint, but no explanation, in microdrive (last paragraph under "Applications"):

"Sometimes when a device with an integrated Microdrive stops working the device is taken apart and stripped of its Microdrive, which is then sold on. Unfortunately Microdrives taken from such devices may not work in digital cameras. The device must be accessed using ATA mode and therefore such drives do not fetch anywhere near as much as CF-enabled Microdrives as they cannot be used in devices that do not support ATA mode."

Is ATA mode part of CF+? DHR 19:48, 21 March 2006 (UTC)

[edit] 'Enhanced' CF cards

Lexar produced (still does?) a line of 'USB Enabled' CompactFlash cards that are compatable with most standard CF devices. The concept with them was to include the USB controller on the CF card so that a less complex/expensive USB cable (called the jumpShot) could be used to read/write the cards with PC and Macintosh computers. These cards were initially produced in 1999~2000.

Unfortunately, some devices that are designed to only support strict adherence to the CF standard cannot use these Lexar cards. (One is the Handspring Visor line of PDAs with a Springboard to CF adaptor.)

[edit] un-delete CompactFlash drive ??

can anyone tell me if I can un-delete a Compactflash card to retrive files from it ?

This turns out to have nothing to do with compact flash. It depends on the filesystem on the drive (VFAT?) and the tools you have. DHR 21:12, 15 May 2006 (UTC)

Removed the word 'existing' from the phrase 'so the existing limitations of ATA were considered acceptable'. The word 'existing' in this context was redundant. Krymzn

[edit] CF Card operation and life expectancy?

The article should mention how a CF card actually stores data (at the bit level) and what the (expected) life-expectancy of a CF card should also be mentioned.

I was surprised at the lack of technical content in this article.

Jul. 23, 2006

[edit] 64gb announcment

I read that this article got bit and bytes mixed up. Might be worth looking into.

What do you mean? It means 64 gigabytes. The press release says:

"The 32Gb NAND flash memory can be used in memory cards with densities of up to 64-Gigabytes (GBs). One 64GB card can store over 64 hours of DVD resolution movies (40 movies) or 16,000 MP3 music files (1,340 hours)."

And please sign your comments. ---Majestic- 21:42, 5 October 2006 (UTC)

I removed the sentance "On September 11th, 2006 Samsung announced 32 GB and 64 GB CompactFlash card models[1]. These cards are based on a new technology that will make cards up to 256 GB possible." Read the release, samsung announced 64 gigabit NAND memory chips, no where did they mention compact flash cards (well, there was that picture of CF cards at the top of the page, which probably lead to the confusion). These are higher capacity memory chips, which will likely make it into higher capacity CF cards eventually, increasing the maximum size. Samsung doesn't even make CF cards any more AFK, they make the memory chips for them. BTW I believe current 8gigabyte CF cards are based on 16gigabit chips.74.71.28.125 03:27, 9 November 2006 (UTC)

[edit] Price?

Can someone tell me the price for these CompactFlashes? like for a 128MB one to like a 10 GB one? To compare please? Josh215 14:40, 25 November 2006 (UTC)

[edit] 16 Bit Versus 32 Bit Buses

While this article does make it clear that there are two forms of CF cards more or less corresponding to the PCMCIA Type I and PCMCIA Type II cards, it is ambiguous about the bus organization of the cards. Is there a variation in bus specs for CF cards? Are some of them 16-bit and some of them 32-bit? I would guess that they all but universally support 32-bit 33 MHz CardBus these days, but my guesswork is too often wrong to be relied upon. Some clarification would be nice.

Also, the comment on "PCMCIA-ATA" seems confusing, all the more so because the WKPD article on PCMCIA doesn't mention ATA and the ATA article doesn't mention PCMCIA. Again, clarification might be nice.

MrG / (08 DEC 06) —The preceding unsigned comment was added by 4.228.21.104 (talk) 01:41, 9 December 2006 (UTC).

AFAIK, CF is a small formfactor PC Card, it's 16bit. PC Card is just the AT bus in a small card formfactor. IDE is just the 16bit AT bus extended off on a ribbon to your harddrive. So a CF device is an ISA expansion card in most respects. (An IDE/ATA harddrive is an ISA expansion card in many respects) controllers are onboard the CF card. 132.205.93.63 01:57, 13 June 2007 (UTC)

[edit] Unclear statement

That is, it appears to the host device as if it were a hard disk of some defined size and has a tiny IDE controller onboard the CF device itself

Does a CompactFlash device appear to have an impossibly tiny IDE controller, or does it actually have an IDE controller which is unusually small? —Michael Z. 2007-01-05 02:36 Z

[edit] Frame counters

The article currently has:

With large-capacity cards, some cameras' frame counters may misbehave. For example, the Canon EOS 10D's frame counter displays "999" when a card has room for 1,000 or more photos remaining.

This is the documented behaviour: the counter only has three digits so showing 999 means "999 or more." You can argue whether this is the best UI or not, but it's not a misbehaviour caused by large CF cards. So I might remove it. Subsolar 11:28, 2 May 2007 (UTC)

[edit] relationship

It's rather unclear that CF is a development of PCMCIA in this article. Could someone rewrite it to indicate why CF type 1 and CF type 2 are exactly like PCMCIA type 1 and type 2, down to the electrical interface, and protocol? (or that PCMCIA itself is just the AT bus, IIRC) 132.205.93.63 02:00, 13 June 2007 (UTC)

[edit] Pin-out

It would be nice if the pin-out was added to the article. . . and how it compares to similar pin-outs, like for 1.8 HDDs. - Gus ^{(T, C)} 2007-07-03 17:04Z 17:04, 3 July 2007 (UTC)

while we're on pins, how about a photo of the "business end"? --Kvuo 23:37, 17 July 2007 (UTC)

I've added an external link pointing to a complete CompactFlash connector schematic and pinout. From the linked page is also possible to download the complete specifications. --Nicolaasuni (talk) 17:59, 15 April 2008 (UTC)

[edit] Performance Citation

The main article needs a citation for performance. This site CF/SD Performance Database has performance benchmark on CF cards with Canon cameras. This site clearly shows that the smaller 2G card is faster then the 4G card as this article states. -dain 17:23, 30 July 2007 (UTC)

[edit] Other uses

Many of the latest generation of casino slot machines have their software on CompactFlash cards due to the security precautions of encasing the logic boards in full metal shields. The CF is accessed via a slot in the shielding. (Seen in a recent episode of "How it's Made".)

This came about due to a person who obtained a machine a few years ago and figured out a way to open the front without triggering the door open switch, then subverted the programming by holding a custom chip against the logic board via a curved piece of spring steel. Using a pair of accomplices to block security cameras, he was able to steal thousands of dollars.(Referenced from an episode of The History Channel series "Breaking Vegas".) —Preceding unsigned comment added by Bizzybody (talk • contribs) 08:40, 2 October 2007 (UTC)

[edit] Citations

I think this article could use a few more citations. By request, here a couple examples of what I think should be cited: "Commons knowledge" obviously doesn't have to be, but historical statements like "This form was first specified and produced by SanDisk in 1994." or the paragraph starting with "CF was among the first flash memory standards to compete ..." should probably be referenced.

Also, market-share-related or any other kind of fuzzy statement (e.g. containing words like "many") should get some verification: "However, a CF interface continues to be offered on many devices, and remains the main standard for professional cameras, as well as a number of consumer models as of 2005." "Samsung has launched 16, 32 and 64 GB CF cards however these are not sold under the Samsung brand." etc. That is, anything that's not hard technical facts that anyone can easily google up to verify them. -- Ddxc (talk) 21:46, 12 January 2008 (UTC)

[edit] Links are messed up

so the link [11] is dead, but the link [12] seems to have the content that link #11 should have. but I am not sure because I dont know what link #11 contained before death..

--217.82.39.148 (talk) 13:55, 4 May 2008 (UTC)